1 // Copyright 2015 The Go Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style
3 // license that can be found in the LICENSE file.
4
5 // Simplifications that apply to all backend architectures. As an example, this
6 // Go source code
7 //
8 // y := 0 * x
9 //
10 // can be translated into y := 0 without losing any information, which saves a
11 // pointless multiplication instruction. Other .rules files in this directory
12 // (for example AMD64.rules) contain rules specific to the architecture in the
13 // filename. The rules here apply to every architecture.
14 //
15 // The code for parsing this file lives in rulegen.go; this file generates
16 // ssa/rewritegeneric.go.
17
18 // values are specified using the following format:
19 // (op <type> [auxint] {aux} arg0 arg1 ...)
20 // the type, aux, and auxint fields are optional
21 // on the matching side
22 // - the type, aux, and auxint fields must match if they are specified.
23 // - the first occurrence of a variable defines that variable. Subsequent
24 // uses must match (be == to) the first use.
25 // - v is defined to be the value matched.
26 // - an additional conditional can be provided after the match pattern with "&&".
27 // on the generated side
28 // - the type of the top-level expression is the same as the one on the left-hand side.
29 // - the type of any subexpressions must be specified explicitly (or
30 // be specified in the op's type field).
31 // - auxint will be 0 if not specified.
32 // - aux will be nil if not specified.
33
34 // blocks are specified using the following format:
35 // (kind controlvalue succ0 succ1 ...)
36 // controlvalue must be "nil" or a value expression
37 // succ* fields must be variables
38 // For now, the generated successors must be a permutation of the matched successors.
39
40 // constant folding
41 (Trunc16to8 (Const16 [c])) => (Const8 [int8(c)])
42 (Trunc32to8 (Const32 [c])) => (Const8 [int8(c)])
43 (Trunc32to16 (Const32 [c])) => (Const16 [int16(c)])
44 (Trunc64to8 (Const64 [c])) => (Const8 [int8(c)])
45 (Trunc64to16 (Const64 [c])) => (Const16 [int16(c)])
46 (Trunc64to32 (Const64 [c])) => (Const32 [int32(c)])
47 (Cvt64Fto32F (Const64F [c])) => (Const32F [float32(c)])
48 (Cvt32Fto64F (Const32F [c])) => (Const64F [float64(c)])
49 (Cvt32to32F (Const32 [c])) => (Const32F [float32(c)])
50 (Cvt32to64F (Const32 [c])) => (Const64F [float64(c)])
51 (Cvt64to32F (Const64 [c])) => (Const32F [float32(c)])
52 (Cvt64to64F (Const64 [c])) => (Const64F [float64(c)])
53 (Cvt32Fto32 (Const32F [c])) => (Const32 [int32(c)])
54 (Cvt32Fto64 (Const32F [c])) => (Const64 [int64(c)])
55 (Cvt64Fto32 (Const64F [c])) => (Const32 [int32(c)])
56 (Cvt64Fto64 (Const64F [c])) => (Const64 [int64(c)])
57 (Round32F x:(Const32F)) => x
58 (Round64F x:(Const64F)) => x
59 (CvtBoolToUint8 (ConstBool [false])) => (Const8 [0])
60 (CvtBoolToUint8 (ConstBool [true])) => (Const8 [1])
61 (BitLen64 (Const64 [c])) && config.PtrSize == 8 => (Const64 [int64(bits.Len64(uint64(c)))])
62 (BitLen32 (Const32 [c])) && config.PtrSize == 8 => (Const64 [int64(bits.Len32(uint32(c)))])
63 (BitLen16 (Const16 [c])) && config.PtrSize == 8 => (Const64 [int64(bits.Len16(uint16(c)))])
64 (BitLen8 (Const8 [c])) && config.PtrSize == 8 => (Const64 [int64(bits.Len8(uint8(c)))])
65 (BitLen64 (Const64 [c])) && config.PtrSize == 4 => (Const32 [int32(bits.Len64(uint64(c)))])
66 (BitLen32 (Const32 [c])) && config.PtrSize == 4 => (Const32 [int32(bits.Len32(uint32(c)))])
67 (BitLen16 (Const16 [c])) && config.PtrSize == 4 => (Const32 [int32(bits.Len16(uint16(c)))])
68 (BitLen8 (Const8 [c])) && config.PtrSize == 4 => (Const32 [int32(bits.Len8(uint8(c)))])
69 (PopCount64 (Const64 [c])) && config.PtrSize == 8 => (Const64 [int64(bits.OnesCount64(uint64(c)))])
70 (PopCount32 (Const32 [c])) && config.PtrSize == 8 => (Const64 [int64(bits.OnesCount32(uint32(c)))])
71 (PopCount16 (Const16 [c])) && config.PtrSize == 8 => (Const64 [int64(bits.OnesCount16(uint16(c)))])
72 (PopCount8 (Const8 [c])) && config.PtrSize == 8 => (Const64 [int64(bits.OnesCount8(uint8(c)))])
73 (PopCount64 (Const64 [c])) && config.PtrSize == 4 => (Const32 [int32(bits.OnesCount64(uint64(c)))])
74 (PopCount32 (Const32 [c])) && config.PtrSize == 4 => (Const32 [int32(bits.OnesCount32(uint32(c)))])
75 (PopCount16 (Const16 [c])) && config.PtrSize == 4 => (Const32 [int32(bits.OnesCount16(uint16(c)))])
76 (PopCount8 (Const8 [c])) && config.PtrSize == 4 => (Const32 [int32(bits.OnesCount8(uint8(c)))])
77 (Add64carry (Const64 <t> [x]) (Const64 [y]) (Const64 [c])) && c >= 0 && c <= 1 => (MakeTuple (Const64 <t> [bitsAdd64(x, y, c).sum]) (Const64 <t> [bitsAdd64(x, y, c).carry]))
78
79 (Trunc16to8 (ZeroExt8to16 x)) => x
80 (Trunc32to8 (ZeroExt8to32 x)) => x
81 (Trunc32to16 (ZeroExt8to32 x)) => (ZeroExt8to16 x)
82 (Trunc32to16 (ZeroExt16to32 x)) => x
83 (Trunc64to8 (ZeroExt8to64 x)) => x
84 (Trunc64to16 (ZeroExt8to64 x)) => (ZeroExt8to16 x)
85 (Trunc64to16 (ZeroExt16to64 x)) => x
86 (Trunc64to32 (ZeroExt8to64 x)) => (ZeroExt8to32 x)
87 (Trunc64to32 (ZeroExt16to64 x)) => (ZeroExt16to32 x)
88 (Trunc64to32 (ZeroExt32to64 x)) => x
89 (Trunc16to8 (SignExt8to16 x)) => x
90 (Trunc32to8 (SignExt8to32 x)) => x
91 (Trunc32to16 (SignExt8to32 x)) => (SignExt8to16 x)
92 (Trunc32to16 (SignExt16to32 x)) => x
93 (Trunc64to8 (SignExt8to64 x)) => x
94 (Trunc64to16 (SignExt8to64 x)) => (SignExt8to16 x)
95 (Trunc64to16 (SignExt16to64 x)) => x
96 (Trunc64to32 (SignExt8to64 x)) => (SignExt8to32 x)
97 (Trunc64to32 (SignExt16to64 x)) => (SignExt16to32 x)
98 (Trunc64to32 (SignExt32to64 x)) => x
99
100 (ZeroExt8to16 (Const8 [c])) => (Const16 [int16( uint8(c))])
101 (ZeroExt8to32 (Const8 [c])) => (Const32 [int32( uint8(c))])
102 (ZeroExt8to64 (Const8 [c])) => (Const64 [int64( uint8(c))])
103 (ZeroExt16to32 (Const16 [c])) => (Const32 [int32(uint16(c))])
104 (ZeroExt16to64 (Const16 [c])) => (Const64 [int64(uint16(c))])
105 (ZeroExt32to64 (Const32 [c])) => (Const64 [int64(uint32(c))])
106 (SignExt8to16 (Const8 [c])) => (Const16 [int16(c)])
107 (SignExt8to32 (Const8 [c])) => (Const32 [int32(c)])
108 (SignExt8to64 (Const8 [c])) => (Const64 [int64(c)])
109 (SignExt16to32 (Const16 [c])) => (Const32 [int32(c)])
110 (SignExt16to64 (Const16 [c])) => (Const64 [int64(c)])
111 (SignExt32to64 (Const32 [c])) => (Const64 [int64(c)])
112
113 (Neg8 (Const8 [c])) => (Const8 [-c])
114 (Neg16 (Const16 [c])) => (Const16 [-c])
115 (Neg32 (Const32 [c])) => (Const32 [-c])
116 (Neg64 (Const64 [c])) => (Const64 [-c])
117 (Neg32F (Const32F [c])) && c != 0 => (Const32F [-c])
118 (Neg64F (Const64F [c])) && c != 0 => (Const64F [-c])
119
120 (Add8 (Const8 [c]) (Const8 [d])) => (Const8 [c+d])
121 (Add16 (Const16 [c]) (Const16 [d])) => (Const16 [c+d])
122 (Add32 (Const32 [c]) (Const32 [d])) => (Const32 [c+d])
123 (Add64 (Const64 [c]) (Const64 [d])) => (Const64 [c+d])
124 (Add32F (Const32F [c]) (Const32F [d])) && c+d == c+d => (Const32F [c+d])
125 (Add64F (Const64F [c]) (Const64F [d])) && c+d == c+d => (Const64F [c+d])
126 (AddPtr <t> x (Const64 [c])) => (OffPtr <t> x [c])
127 (AddPtr <t> x (Const32 [c])) => (OffPtr <t> x [int64(c)])
128
129 (Sub8 (Const8 [c]) (Const8 [d])) => (Const8 [c-d])
130 (Sub16 (Const16 [c]) (Const16 [d])) => (Const16 [c-d])
131 (Sub32 (Const32 [c]) (Const32 [d])) => (Const32 [c-d])
132 (Sub64 (Const64 [c]) (Const64 [d])) => (Const64 [c-d])
133 (Sub32F (Const32F [c]) (Const32F [d])) && c-d == c-d => (Const32F [c-d])
134 (Sub64F (Const64F [c]) (Const64F [d])) && c-d == c-d => (Const64F [c-d])
135
136 (Mul8 (Const8 [c]) (Const8 [d])) => (Const8 [c*d])
137 (Mul16 (Const16 [c]) (Const16 [d])) => (Const16 [c*d])
138 (Mul32 (Const32 [c]) (Const32 [d])) => (Const32 [c*d])
139 (Mul64 (Const64 [c]) (Const64 [d])) => (Const64 [c*d])
140 (Mul32F (Const32F [c]) (Const32F [d])) && c*d == c*d => (Const32F [c*d])
141 (Mul64F (Const64F [c]) (Const64F [d])) && c*d == c*d => (Const64F [c*d])
142
143 (And8 (Const8 [c]) (Const8 [d])) => (Const8 [c&d])
144 (And16 (Const16 [c]) (Const16 [d])) => (Const16 [c&d])
145 (And32 (Const32 [c]) (Const32 [d])) => (Const32 [c&d])
146 (And64 (Const64 [c]) (Const64 [d])) => (Const64 [c&d])
147
148 (Or8 (Const8 [c]) (Const8 [d])) => (Const8 [c|d])
149 (Or16 (Const16 [c]) (Const16 [d])) => (Const16 [c|d])
150 (Or32 (Const32 [c]) (Const32 [d])) => (Const32 [c|d])
151 (Or64 (Const64 [c]) (Const64 [d])) => (Const64 [c|d])
152
153 (Xor8 (Const8 [c]) (Const8 [d])) => (Const8 [c^d])
154 (Xor16 (Const16 [c]) (Const16 [d])) => (Const16 [c^d])
155 (Xor32 (Const32 [c]) (Const32 [d])) => (Const32 [c^d])
156 (Xor64 (Const64 [c]) (Const64 [d])) => (Const64 [c^d])
157
158 (Ctz64 (Const64 [c])) && config.PtrSize == 4 => (Const32 [int32(ntz64(c))])
159 (Ctz32 (Const32 [c])) && config.PtrSize == 4 => (Const32 [int32(ntz32(c))])
160 (Ctz16 (Const16 [c])) && config.PtrSize == 4 => (Const32 [int32(ntz16(c))])
161 (Ctz8 (Const8 [c])) && config.PtrSize == 4 => (Const32 [int32(ntz8(c))])
162
163 (Ctz64 (Const64 [c])) && config.PtrSize == 8 => (Const64 [int64(ntz64(c))])
164 (Ctz32 (Const32 [c])) && config.PtrSize == 8 => (Const64 [int64(ntz32(c))])
165 (Ctz16 (Const16 [c])) && config.PtrSize == 8 => (Const64 [int64(ntz16(c))])
166 (Ctz8 (Const8 [c])) && config.PtrSize == 8 => (Const64 [int64(ntz8(c))])
167
168 (Div8 (Const8 [c]) (Const8 [d])) && d != 0 => (Const8 [c/d])
169 (Div16 (Const16 [c]) (Const16 [d])) && d != 0 => (Const16 [c/d])
170 (Div32 (Const32 [c]) (Const32 [d])) && d != 0 => (Const32 [c/d])
171 (Div64 (Const64 [c]) (Const64 [d])) && d != 0 => (Const64 [c/d])
172 (Div8u (Const8 [c]) (Const8 [d])) && d != 0 => (Const8 [int8(uint8(c)/uint8(d))])
173 (Div16u (Const16 [c]) (Const16 [d])) && d != 0 => (Const16 [int16(uint16(c)/uint16(d))])
174 (Div32u (Const32 [c]) (Const32 [d])) && d != 0 => (Const32 [int32(uint32(c)/uint32(d))])
175 (Div64u (Const64 [c]) (Const64 [d])) && d != 0 => (Const64 [int64(uint64(c)/uint64(d))])
176 (Div32F (Const32F [c]) (Const32F [d])) && c/d == c/d => (Const32F [c/d])
177 (Div64F (Const64F [c]) (Const64F [d])) && c/d == c/d => (Const64F [c/d])
178 (Div128u <t> (Const64 [0]) lo y) => (MakeTuple (Div64u <t.FieldType(0)> lo y) (Mod64u <t.FieldType(1)> lo y))
179
180 (Not (ConstBool [c])) => (ConstBool [!c])
181
182 (Floor (Const64F [c])) => (Const64F [math.Floor(c)])
183 (Ceil (Const64F [c])) => (Const64F [math.Ceil(c)])
184 (Trunc (Const64F [c])) => (Const64F [math.Trunc(c)])
185 (RoundToEven (Const64F [c])) => (Const64F [math.RoundToEven(c)])
186
187 // Convert x * 1 to x.
188 (Mul(8|16|32|64) (Const(8|16|32|64) [1]) x) => x
189 (Mul(32|64)uover <t> (Const(32|64) [1]) x) => (MakeTuple x (ConstBool <t.FieldType(1)> [false]))
190
191 // Convert x * -1 to -x.
192 (Mul(8|16|32|64) (Const(8|16|32|64) [-1]) x) => (Neg(8|16|32|64) x)
193
194 // DeMorgan's Laws
195 (And(8|16|32|64) <t> (Com(8|16|32|64) x) (Com(8|16|32|64) y)) => (Com(8|16|32|64) (Or(8|16|32|64) <t> x y))
196 (Or(8|16|32|64) <t> (Com(8|16|32|64) x) (Com(8|16|32|64) y)) => (Com(8|16|32|64) (And(8|16|32|64) <t> x y))
197
198 // Convert multiplication by a power of two to a shift.
199 (Mul8 <t> n (Const8 [c])) && isPowerOfTwo(c) => (Lsh8x64 <t> n (Const64 <typ.UInt64> [log8(c)]))
200 (Mul16 <t> n (Const16 [c])) && isPowerOfTwo(c) => (Lsh16x64 <t> n (Const64 <typ.UInt64> [log16(c)]))
201 (Mul32 <t> n (Const32 [c])) && isPowerOfTwo(c) => (Lsh32x64 <t> n (Const64 <typ.UInt64> [log32(c)]))
202 (Mul64 <t> n (Const64 [c])) && isPowerOfTwo(c) => (Lsh64x64 <t> n (Const64 <typ.UInt64> [log64(c)]))
203 (Mul8 <t> n (Const8 [c])) && t.IsSigned() && isPowerOfTwo(-c) => (Neg8 (Lsh8x64 <t> n (Const64 <typ.UInt64> [log8(-c)])))
204 (Mul16 <t> n (Const16 [c])) && t.IsSigned() && isPowerOfTwo(-c) => (Neg16 (Lsh16x64 <t> n (Const64 <typ.UInt64> [log16(-c)])))
205 (Mul32 <t> n (Const32 [c])) && t.IsSigned() && isPowerOfTwo(-c) => (Neg32 (Lsh32x64 <t> n (Const64 <typ.UInt64> [log32(-c)])))
206 (Mul64 <t> n (Const64 [c])) && t.IsSigned() && isPowerOfTwo(-c) => (Neg64 (Lsh64x64 <t> n (Const64 <typ.UInt64> [log64(-c)])))
207
208 (Mod8 (Const8 [c]) (Const8 [d])) && d != 0 => (Const8 [c % d])
209 (Mod16 (Const16 [c]) (Const16 [d])) && d != 0 => (Const16 [c % d])
210 (Mod32 (Const32 [c]) (Const32 [d])) && d != 0 => (Const32 [c % d])
211 (Mod64 (Const64 [c]) (Const64 [d])) && d != 0 => (Const64 [c % d])
212
213 (Mod8u (Const8 [c]) (Const8 [d])) && d != 0 => (Const8 [int8(uint8(c) % uint8(d))])
214 (Mod16u (Const16 [c]) (Const16 [d])) && d != 0 => (Const16 [int16(uint16(c) % uint16(d))])
215 (Mod32u (Const32 [c]) (Const32 [d])) && d != 0 => (Const32 [int32(uint32(c) % uint32(d))])
216 (Mod64u (Const64 [c]) (Const64 [d])) && d != 0 => (Const64 [int64(uint64(c) % uint64(d))])
217
218 (Lsh64x64 (Const64 [c]) (Const64 [d])) => (Const64 [c << uint64(d)])
219 (Rsh64x64 (Const64 [c]) (Const64 [d])) => (Const64 [c >> uint64(d)])
220 (Rsh64Ux64 (Const64 [c]) (Const64 [d])) => (Const64 [int64(uint64(c) >> uint64(d))])
221 (Lsh32x64 (Const32 [c]) (Const64 [d])) => (Const32 [c << uint64(d)])
222 (Rsh32x64 (Const32 [c]) (Const64 [d])) => (Const32 [c >> uint64(d)])
223 (Rsh32Ux64 (Const32 [c]) (Const64 [d])) => (Const32 [int32(uint32(c) >> uint64(d))])
224 (Lsh16x64 (Const16 [c]) (Const64 [d])) => (Const16 [c << uint64(d)])
225 (Rsh16x64 (Const16 [c]) (Const64 [d])) => (Const16 [c >> uint64(d)])
226 (Rsh16Ux64 (Const16 [c]) (Const64 [d])) => (Const16 [int16(uint16(c) >> uint64(d))])
227 (Lsh8x64 (Const8 [c]) (Const64 [d])) => (Const8 [c << uint64(d)])
228 (Rsh8x64 (Const8 [c]) (Const64 [d])) => (Const8 [c >> uint64(d)])
229 (Rsh8Ux64 (Const8 [c]) (Const64 [d])) => (Const8 [int8(uint8(c) >> uint64(d))])
230
231 // Fold IsInBounds when the range of the index cannot exceed the limit.
232 (IsInBounds (ZeroExt8to32 _) (Const32 [c])) && (1 << 8) <= c => (ConstBool [true])
233 (IsInBounds (ZeroExt8to64 _) (Const64 [c])) && (1 << 8) <= c => (ConstBool [true])
234 (IsInBounds (ZeroExt16to32 _) (Const32 [c])) && (1 << 16) <= c => (ConstBool [true])
235 (IsInBounds (ZeroExt16to64 _) (Const64 [c])) && (1 << 16) <= c => (ConstBool [true])
236 (IsInBounds x x) => (ConstBool [false])
237 (IsInBounds (And8 (Const8 [c]) _) (Const8 [d])) && 0 <= c && c < d => (ConstBool [true])
238 (IsInBounds (ZeroExt8to16 (And8 (Const8 [c]) _)) (Const16 [d])) && 0 <= c && int16(c) < d => (ConstBool [true])
239 (IsInBounds (ZeroExt8to32 (And8 (Const8 [c]) _)) (Const32 [d])) && 0 <= c && int32(c) < d => (ConstBool [true])
240 (IsInBounds (ZeroExt8to64 (And8 (Const8 [c]) _)) (Const64 [d])) && 0 <= c && int64(c) < d => (ConstBool [true])
241 (IsInBounds (And16 (Const16 [c]) _) (Const16 [d])) && 0 <= c && c < d => (ConstBool [true])
242 (IsInBounds (ZeroExt16to32 (And16 (Const16 [c]) _)) (Const32 [d])) && 0 <= c && int32(c) < d => (ConstBool [true])
243 (IsInBounds (ZeroExt16to64 (And16 (Const16 [c]) _)) (Const64 [d])) && 0 <= c && int64(c) < d => (ConstBool [true])
244 (IsInBounds (And32 (Const32 [c]) _) (Const32 [d])) && 0 <= c && c < d => (ConstBool [true])
245 (IsInBounds (ZeroExt32to64 (And32 (Const32 [c]) _)) (Const64 [d])) && 0 <= c && int64(c) < d => (ConstBool [true])
246 (IsInBounds (And64 (Const64 [c]) _) (Const64 [d])) && 0 <= c && c < d => (ConstBool [true])
247 (IsInBounds (Const32 [c]) (Const32 [d])) => (ConstBool [0 <= c && c < d])
248 (IsInBounds (Const64 [c]) (Const64 [d])) => (ConstBool [0 <= c && c < d])
249 // (Mod64u x y) is always between 0 (inclusive) and y (exclusive).
250 (IsInBounds (Mod32u _ y) y) => (ConstBool [true])
251 (IsInBounds (Mod64u _ y) y) => (ConstBool [true])
252 // Right shifting an unsigned number limits its value.
253 (IsInBounds (ZeroExt8to64 (Rsh8Ux64 _ (Const64 [c]))) (Const64 [d])) && 0 < c && c < 8 && 1<<uint( 8-c)-1 < d => (ConstBool [true])
254 (IsInBounds (ZeroExt8to32 (Rsh8Ux64 _ (Const64 [c]))) (Const32 [d])) && 0 < c && c < 8 && 1<<uint( 8-c)-1 < d => (ConstBool [true])
255 (IsInBounds (ZeroExt8to16 (Rsh8Ux64 _ (Const64 [c]))) (Const16 [d])) && 0 < c && c < 8 && 1<<uint( 8-c)-1 < d => (ConstBool [true])
256 (IsInBounds (Rsh8Ux64 _ (Const64 [c])) (Const64 [d])) && 0 < c && c < 8 && 1<<uint( 8-c)-1 < d => (ConstBool [true])
257 (IsInBounds (ZeroExt16to64 (Rsh16Ux64 _ (Const64 [c]))) (Const64 [d])) && 0 < c && c < 16 && 1<<uint(16-c)-1 < d => (ConstBool [true])
258 (IsInBounds (ZeroExt16to32 (Rsh16Ux64 _ (Const64 [c]))) (Const64 [d])) && 0 < c && c < 16 && 1<<uint(16-c)-1 < d => (ConstBool [true])
259 (IsInBounds (Rsh16Ux64 _ (Const64 [c])) (Const64 [d])) && 0 < c && c < 16 && 1<<uint(16-c)-1 < d => (ConstBool [true])
260 (IsInBounds (ZeroExt32to64 (Rsh32Ux64 _ (Const64 [c]))) (Const64 [d])) && 0 < c && c < 32 && 1<<uint(32-c)-1 < d => (ConstBool [true])
261 (IsInBounds (Rsh32Ux64 _ (Const64 [c])) (Const64 [d])) && 0 < c && c < 32 && 1<<uint(32-c)-1 < d => (ConstBool [true])
262 (IsInBounds (Rsh64Ux64 _ (Const64 [c])) (Const64 [d])) && 0 < c && c < 64 && 1<<uint(64-c)-1 < d => (ConstBool [true])
263
264 (IsSliceInBounds x x) => (ConstBool [true])
265 (IsSliceInBounds (And32 (Const32 [c]) _) (Const32 [d])) && 0 <= c && c <= d => (ConstBool [true])
266 (IsSliceInBounds (And64 (Const64 [c]) _) (Const64 [d])) && 0 <= c && c <= d => (ConstBool [true])
267 (IsSliceInBounds (Const32 [0]) _) => (ConstBool [true])
268 (IsSliceInBounds (Const64 [0]) _) => (ConstBool [true])
269 (IsSliceInBounds (Const32 [c]) (Const32 [d])) => (ConstBool [0 <= c && c <= d])
270 (IsSliceInBounds (Const64 [c]) (Const64 [d])) => (ConstBool [0 <= c && c <= d])
271 (IsSliceInBounds (SliceLen x) (SliceCap x)) => (ConstBool [true])
272
273 (Eq(64|32|16|8) x x) => (ConstBool [true])
274 (EqB (ConstBool [c]) (ConstBool [d])) => (ConstBool [c == d])
275 (EqB (ConstBool [false]) x) => (Not x)
276 (EqB (ConstBool [true]) x) => x
277
278 (Neq(64|32|16|8) x x) => (ConstBool [false])
279 (NeqB (ConstBool [c]) (ConstBool [d])) => (ConstBool [c != d])
280 (NeqB (ConstBool [false]) x) => x
281 (NeqB (ConstBool [true]) x) => (Not x)
282 (NeqB (Not x) (Not y)) => (NeqB x y)
283
284 (Eq64 (Const64 <t> [c]) (Add64 (Const64 <t> [d]) x)) => (Eq64 (Const64 <t> [c-d]) x)
285 (Eq32 (Const32 <t> [c]) (Add32 (Const32 <t> [d]) x)) => (Eq32 (Const32 <t> [c-d]) x)
286 (Eq16 (Const16 <t> [c]) (Add16 (Const16 <t> [d]) x)) => (Eq16 (Const16 <t> [c-d]) x)
287 (Eq8 (Const8 <t> [c]) (Add8 (Const8 <t> [d]) x)) => (Eq8 (Const8 <t> [c-d]) x)
288
289 (Neq64 (Const64 <t> [c]) (Add64 (Const64 <t> [d]) x)) => (Neq64 (Const64 <t> [c-d]) x)
290 (Neq32 (Const32 <t> [c]) (Add32 (Const32 <t> [d]) x)) => (Neq32 (Const32 <t> [c-d]) x)
291 (Neq16 (Const16 <t> [c]) (Add16 (Const16 <t> [d]) x)) => (Neq16 (Const16 <t> [c-d]) x)
292 (Neq8 (Const8 <t> [c]) (Add8 (Const8 <t> [d]) x)) => (Neq8 (Const8 <t> [c-d]) x)
293
294 // signed integer range: ( c <= x && x (<|<=) d ) -> ( unsigned(x-c) (<|<=) unsigned(d-c) )
295 (AndB (Leq64 (Const64 [c]) x) ((Less|Leq)64 x (Const64 [d]))) && d >= c => ((Less|Leq)64U (Sub64 <x.Type> x (Const64 <x.Type> [c])) (Const64 <x.Type> [d-c]))
296 (AndB (Leq32 (Const32 [c]) x) ((Less|Leq)32 x (Const32 [d]))) && d >= c => ((Less|Leq)32U (Sub32 <x.Type> x (Const32 <x.Type> [c])) (Const32 <x.Type> [d-c]))
297 (AndB (Leq16 (Const16 [c]) x) ((Less|Leq)16 x (Const16 [d]))) && d >= c => ((Less|Leq)16U (Sub16 <x.Type> x (Const16 <x.Type> [c])) (Const16 <x.Type> [d-c]))
298 (AndB (Leq8 (Const8 [c]) x) ((Less|Leq)8 x (Const8 [d]))) && d >= c => ((Less|Leq)8U (Sub8 <x.Type> x (Const8 <x.Type> [c])) (Const8 <x.Type> [d-c]))
299
300 // signed integer range: ( c < x && x (<|<=) d ) -> ( unsigned(x-(c+1)) (<|<=) unsigned(d-(c+1)) )
301 (AndB (Less64 (Const64 [c]) x) ((Less|Leq)64 x (Const64 [d]))) && d >= c+1 && c+1 > c => ((Less|Leq)64U (Sub64 <x.Type> x (Const64 <x.Type> [c+1])) (Const64 <x.Type> [d-c-1]))
302 (AndB (Less32 (Const32 [c]) x) ((Less|Leq)32 x (Const32 [d]))) && d >= c+1 && c+1 > c => ((Less|Leq)32U (Sub32 <x.Type> x (Const32 <x.Type> [c+1])) (Const32 <x.Type> [d-c-1]))
303 (AndB (Less16 (Const16 [c]) x) ((Less|Leq)16 x (Const16 [d]))) && d >= c+1 && c+1 > c => ((Less|Leq)16U (Sub16 <x.Type> x (Const16 <x.Type> [c+1])) (Const16 <x.Type> [d-c-1]))
304 (AndB (Less8 (Const8 [c]) x) ((Less|Leq)8 x (Const8 [d]))) && d >= c+1 && c+1 > c => ((Less|Leq)8U (Sub8 <x.Type> x (Const8 <x.Type> [c+1])) (Const8 <x.Type> [d-c-1]))
305
306 // unsigned integer range: ( c <= x && x (<|<=) d ) -> ( x-c (<|<=) d-c )
307 (AndB (Leq64U (Const64 [c]) x) ((Less|Leq)64U x (Const64 [d]))) && uint64(d) >= uint64(c) => ((Less|Leq)64U (Sub64 <x.Type> x (Const64 <x.Type> [c])) (Const64 <x.Type> [d-c]))
308 (AndB (Leq32U (Const32 [c]) x) ((Less|Leq)32U x (Const32 [d]))) && uint32(d) >= uint32(c) => ((Less|Leq)32U (Sub32 <x.Type> x (Const32 <x.Type> [c])) (Const32 <x.Type> [d-c]))
309 (AndB (Leq16U (Const16 [c]) x) ((Less|Leq)16U x (Const16 [d]))) && uint16(d) >= uint16(c) => ((Less|Leq)16U (Sub16 <x.Type> x (Const16 <x.Type> [c])) (Const16 <x.Type> [d-c]))
310 (AndB (Leq8U (Const8 [c]) x) ((Less|Leq)8U x (Const8 [d]))) && uint8(d) >= uint8(c) => ((Less|Leq)8U (Sub8 <x.Type> x (Const8 <x.Type> [c])) (Const8 <x.Type> [d-c]))
311
312 // unsigned integer range: ( c < x && x (<|<=) d ) -> ( x-(c+1) (<|<=) d-(c+1) )
313 (AndB (Less64U (Const64 [c]) x) ((Less|Leq)64U x (Const64 [d]))) && uint64(d) >= uint64(c+1) && uint64(c+1) > uint64(c) => ((Less|Leq)64U (Sub64 <x.Type> x (Const64 <x.Type> [c+1])) (Const64 <x.Type> [d-c-1]))
314 (AndB (Less32U (Const32 [c]) x) ((Less|Leq)32U x (Const32 [d]))) && uint32(d) >= uint32(c+1) && uint32(c+1) > uint32(c) => ((Less|Leq)32U (Sub32 <x.Type> x (Const32 <x.Type> [c+1])) (Const32 <x.Type> [d-c-1]))
315 (AndB (Less16U (Const16 [c]) x) ((Less|Leq)16U x (Const16 [d]))) && uint16(d) >= uint16(c+1) && uint16(c+1) > uint16(c) => ((Less|Leq)16U (Sub16 <x.Type> x (Const16 <x.Type> [c+1])) (Const16 <x.Type> [d-c-1]))
316 (AndB (Less8U (Const8 [c]) x) ((Less|Leq)8U x (Const8 [d]))) && uint8(d) >= uint8(c+1) && uint8(c+1) > uint8(c) => ((Less|Leq)8U (Sub8 <x.Type> x (Const8 <x.Type> [c+1])) (Const8 <x.Type> [d-c-1]))
317
318 // signed integer range: ( c (<|<=) x || x < d ) -> ( unsigned(c-d) (<|<=) unsigned(x-d) )
319 (OrB ((Less|Leq)64 (Const64 [c]) x) (Less64 x (Const64 [d]))) && c >= d => ((Less|Leq)64U (Const64 <x.Type> [c-d]) (Sub64 <x.Type> x (Const64 <x.Type> [d])))
320 (OrB ((Less|Leq)32 (Const32 [c]) x) (Less32 x (Const32 [d]))) && c >= d => ((Less|Leq)32U (Const32 <x.Type> [c-d]) (Sub32 <x.Type> x (Const32 <x.Type> [d])))
321 (OrB ((Less|Leq)16 (Const16 [c]) x) (Less16 x (Const16 [d]))) && c >= d => ((Less|Leq)16U (Const16 <x.Type> [c-d]) (Sub16 <x.Type> x (Const16 <x.Type> [d])))
322 (OrB ((Less|Leq)8 (Const8 [c]) x) (Less8 x (Const8 [d]))) && c >= d => ((Less|Leq)8U (Const8 <x.Type> [c-d]) (Sub8 <x.Type> x (Const8 <x.Type> [d])))
323
324 // signed integer range: ( c (<|<=) x || x <= d ) -> ( unsigned(c-(d+1)) (<|<=) unsigned(x-(d+1)) )
325 (OrB ((Less|Leq)64 (Const64 [c]) x) (Leq64 x (Const64 [d]))) && c >= d+1 && d+1 > d => ((Less|Leq)64U (Const64 <x.Type> [c-d-1]) (Sub64 <x.Type> x (Const64 <x.Type> [d+1])))
326 (OrB ((Less|Leq)32 (Const32 [c]) x) (Leq32 x (Const32 [d]))) && c >= d+1 && d+1 > d => ((Less|Leq)32U (Const32 <x.Type> [c-d-1]) (Sub32 <x.Type> x (Const32 <x.Type> [d+1])))
327 (OrB ((Less|Leq)16 (Const16 [c]) x) (Leq16 x (Const16 [d]))) && c >= d+1 && d+1 > d => ((Less|Leq)16U (Const16 <x.Type> [c-d-1]) (Sub16 <x.Type> x (Const16 <x.Type> [d+1])))
328 (OrB ((Less|Leq)8 (Const8 [c]) x) (Leq8 x (Const8 [d]))) && c >= d+1 && d+1 > d => ((Less|Leq)8U (Const8 <x.Type> [c-d-1]) (Sub8 <x.Type> x (Const8 <x.Type> [d+1])))
329
330 // unsigned integer range: ( c (<|<=) x || x < d ) -> ( c-d (<|<=) x-d )
331 (OrB ((Less|Leq)64U (Const64 [c]) x) (Less64U x (Const64 [d]))) && uint64(c) >= uint64(d) => ((Less|Leq)64U (Const64 <x.Type> [c-d]) (Sub64 <x.Type> x (Const64 <x.Type> [d])))
332 (OrB ((Less|Leq)32U (Const32 [c]) x) (Less32U x (Const32 [d]))) && uint32(c) >= uint32(d) => ((Less|Leq)32U (Const32 <x.Type> [c-d]) (Sub32 <x.Type> x (Const32 <x.Type> [d])))
333 (OrB ((Less|Leq)16U (Const16 [c]) x) (Less16U x (Const16 [d]))) && uint16(c) >= uint16(d) => ((Less|Leq)16U (Const16 <x.Type> [c-d]) (Sub16 <x.Type> x (Const16 <x.Type> [d])))
334 (OrB ((Less|Leq)8U (Const8 [c]) x) (Less8U x (Const8 [d]))) && uint8(c) >= uint8(d) => ((Less|Leq)8U (Const8 <x.Type> [c-d]) (Sub8 <x.Type> x (Const8 <x.Type> [d])))
335
336 // unsigned integer range: ( c (<|<=) x || x <= d ) -> ( c-(d+1) (<|<=) x-(d+1) )
337 (OrB ((Less|Leq)64U (Const64 [c]) x) (Leq64U x (Const64 [d]))) && uint64(c) >= uint64(d+1) && uint64(d+1) > uint64(d) => ((Less|Leq)64U (Const64 <x.Type> [c-d-1]) (Sub64 <x.Type> x (Const64 <x.Type> [d+1])))
338 (OrB ((Less|Leq)32U (Const32 [c]) x) (Leq32U x (Const32 [d]))) && uint32(c) >= uint32(d+1) && uint32(d+1) > uint32(d) => ((Less|Leq)32U (Const32 <x.Type> [c-d-1]) (Sub32 <x.Type> x (Const32 <x.Type> [d+1])))
339 (OrB ((Less|Leq)16U (Const16 [c]) x) (Leq16U x (Const16 [d]))) && uint16(c) >= uint16(d+1) && uint16(d+1) > uint16(d) => ((Less|Leq)16U (Const16 <x.Type> [c-d-1]) (Sub16 <x.Type> x (Const16 <x.Type> [d+1])))
340 (OrB ((Less|Leq)8U (Const8 [c]) x) (Leq8U x (Const8 [d]))) && uint8(c) >= uint8(d+1) && uint8(d+1) > uint8(d) => ((Less|Leq)8U (Const8 <x.Type> [c-d-1]) (Sub8 <x.Type> x (Const8 <x.Type> [d+1])))
341
342 // Canonicalize x-const to x+(-const)
343 (Sub64 x (Const64 <t> [c])) && x.Op != OpConst64 => (Add64 (Const64 <t> [-c]) x)
344 (Sub32 x (Const32 <t> [c])) && x.Op != OpConst32 => (Add32 (Const32 <t> [-c]) x)
345 (Sub16 x (Const16 <t> [c])) && x.Op != OpConst16 => (Add16 (Const16 <t> [-c]) x)
346 (Sub8 x (Const8 <t> [c])) && x.Op != OpConst8 => (Add8 (Const8 <t> [-c]) x)
347
348 // fold negation into comparison operators
349 (Not (Eq(64|32|16|8|B|Ptr|64F|32F) x y)) => (Neq(64|32|16|8|B|Ptr|64F|32F) x y)
350 (Not (Neq(64|32|16|8|B|Ptr|64F|32F) x y)) => (Eq(64|32|16|8|B|Ptr|64F|32F) x y)
351
352 (Not (Less(64|32|16|8) x y)) => (Leq(64|32|16|8) y x)
353 (Not (Less(64|32|16|8)U x y)) => (Leq(64|32|16|8)U y x)
354 (Not (Leq(64|32|16|8) x y)) => (Less(64|32|16|8) y x)
355 (Not (Leq(64|32|16|8)U x y)) => (Less(64|32|16|8)U y x)
356
357 // Distribute multiplication c * (d+x) -> c*d + c*x. Useful for:
358 // a[i].b = ...; a[i+1].b = ...
359 (Mul64 (Const64 <t> [c]) (Add64 <t> (Const64 <t> [d]) x)) =>
360 (Add64 (Const64 <t> [c*d]) (Mul64 <t> (Const64 <t> [c]) x))
361 (Mul32 (Const32 <t> [c]) (Add32 <t> (Const32 <t> [d]) x)) =>
362 (Add32 (Const32 <t> [c*d]) (Mul32 <t> (Const32 <t> [c]) x))
363 (Mul16 (Const16 <t> [c]) (Add16 <t> (Const16 <t> [d]) x)) =>
364 (Add16 (Const16 <t> [c*d]) (Mul16 <t> (Const16 <t> [c]) x))
365 (Mul8 (Const8 <t> [c]) (Add8 <t> (Const8 <t> [d]) x)) =>
366 (Add8 (Const8 <t> [c*d]) (Mul8 <t> (Const8 <t> [c]) x))
367
368 // Rewrite x*y ± x*z to x*(y±z)
369 (Add(64|32|16|8) <t> (Mul(64|32|16|8) x y) (Mul(64|32|16|8) x z))
370 => (Mul(64|32|16|8) x (Add(64|32|16|8) <t> y z))
371 (Sub(64|32|16|8) <t> (Mul(64|32|16|8) x y) (Mul(64|32|16|8) x z))
372 => (Mul(64|32|16|8) x (Sub(64|32|16|8) <t> y z))
373
374 // rewrite shifts of 8/16/32 bit consts into 64 bit consts to reduce
375 // the number of the other rewrite rules for const shifts
376 (Lsh64x32 <t> x (Const32 [c])) => (Lsh64x64 x (Const64 <t> [int64(uint32(c))]))
377 (Lsh64x16 <t> x (Const16 [c])) => (Lsh64x64 x (Const64 <t> [int64(uint16(c))]))
378 (Lsh64x8 <t> x (Const8 [c])) => (Lsh64x64 x (Const64 <t> [int64(uint8(c))]))
379 (Rsh64x32 <t> x (Const32 [c])) => (Rsh64x64 x (Const64 <t> [int64(uint32(c))]))
380 (Rsh64x16 <t> x (Const16 [c])) => (Rsh64x64 x (Const64 <t> [int64(uint16(c))]))
381 (Rsh64x8 <t> x (Const8 [c])) => (Rsh64x64 x (Const64 <t> [int64(uint8(c))]))
382 (Rsh64Ux32 <t> x (Const32 [c])) => (Rsh64Ux64 x (Const64 <t> [int64(uint32(c))]))
383 (Rsh64Ux16 <t> x (Const16 [c])) => (Rsh64Ux64 x (Const64 <t> [int64(uint16(c))]))
384 (Rsh64Ux8 <t> x (Const8 [c])) => (Rsh64Ux64 x (Const64 <t> [int64(uint8(c))]))
385
386 (Lsh32x32 <t> x (Const32 [c])) => (Lsh32x64 x (Const64 <t> [int64(uint32(c))]))
387 (Lsh32x16 <t> x (Const16 [c])) => (Lsh32x64 x (Const64 <t> [int64(uint16(c))]))
388 (Lsh32x8 <t> x (Const8 [c])) => (Lsh32x64 x (Const64 <t> [int64(uint8(c))]))
389 (Rsh32x32 <t> x (Const32 [c])) => (Rsh32x64 x (Const64 <t> [int64(uint32(c))]))
390 (Rsh32x16 <t> x (Const16 [c])) => (Rsh32x64 x (Const64 <t> [int64(uint16(c))]))
391 (Rsh32x8 <t> x (Const8 [c])) => (Rsh32x64 x (Const64 <t> [int64(uint8(c))]))
392 (Rsh32Ux32 <t> x (Const32 [c])) => (Rsh32Ux64 x (Const64 <t> [int64(uint32(c))]))
393 (Rsh32Ux16 <t> x (Const16 [c])) => (Rsh32Ux64 x (Const64 <t> [int64(uint16(c))]))
394 (Rsh32Ux8 <t> x (Const8 [c])) => (Rsh32Ux64 x (Const64 <t> [int64(uint8(c))]))
395
396 (Lsh16x32 <t> x (Const32 [c])) => (Lsh16x64 x (Const64 <t> [int64(uint32(c))]))
397 (Lsh16x16 <t> x (Const16 [c])) => (Lsh16x64 x (Const64 <t> [int64(uint16(c))]))
398 (Lsh16x8 <t> x (Const8 [c])) => (Lsh16x64 x (Const64 <t> [int64(uint8(c))]))
399 (Rsh16x32 <t> x (Const32 [c])) => (Rsh16x64 x (Const64 <t> [int64(uint32(c))]))
400 (Rsh16x16 <t> x (Const16 [c])) => (Rsh16x64 x (Const64 <t> [int64(uint16(c))]))
401 (Rsh16x8 <t> x (Const8 [c])) => (Rsh16x64 x (Const64 <t> [int64(uint8(c))]))
402 (Rsh16Ux32 <t> x (Const32 [c])) => (Rsh16Ux64 x (Const64 <t> [int64(uint32(c))]))
403 (Rsh16Ux16 <t> x (Const16 [c])) => (Rsh16Ux64 x (Const64 <t> [int64(uint16(c))]))
404 (Rsh16Ux8 <t> x (Const8 [c])) => (Rsh16Ux64 x (Const64 <t> [int64(uint8(c))]))
405
406 (Lsh8x32 <t> x (Const32 [c])) => (Lsh8x64 x (Const64 <t> [int64(uint32(c))]))
407 (Lsh8x16 <t> x (Const16 [c])) => (Lsh8x64 x (Const64 <t> [int64(uint16(c))]))
408 (Lsh8x8 <t> x (Const8 [c])) => (Lsh8x64 x (Const64 <t> [int64(uint8(c))]))
409 (Rsh8x32 <t> x (Const32 [c])) => (Rsh8x64 x (Const64 <t> [int64(uint32(c))]))
410 (Rsh8x16 <t> x (Const16 [c])) => (Rsh8x64 x (Const64 <t> [int64(uint16(c))]))
411 (Rsh8x8 <t> x (Const8 [c])) => (Rsh8x64 x (Const64 <t> [int64(uint8(c))]))
412 (Rsh8Ux32 <t> x (Const32 [c])) => (Rsh8Ux64 x (Const64 <t> [int64(uint32(c))]))
413 (Rsh8Ux16 <t> x (Const16 [c])) => (Rsh8Ux64 x (Const64 <t> [int64(uint16(c))]))
414 (Rsh8Ux8 <t> x (Const8 [c])) => (Rsh8Ux64 x (Const64 <t> [int64(uint8(c))]))
415
416 // shifts by zero
417 (Lsh(64|32|16|8)x64 x (Const64 [0])) => x
418 (Rsh(64|32|16|8)x64 x (Const64 [0])) => x
419 (Rsh(64|32|16|8)Ux64 x (Const64 [0])) => x
420
421 // rotates by multiples of register width
422 (RotateLeft64 x (Const64 [c])) && c%64 == 0 => x
423 (RotateLeft32 x (Const32 [c])) && c%32 == 0 => x
424 (RotateLeft16 x (Const16 [c])) && c%16 == 0 => x
425 (RotateLeft8 x (Const8 [c])) && c%8 == 0 => x
426
427 // zero shifted
428 (Lsh64x(64|32|16|8) (Const64 [0]) _) => (Const64 [0])
429 (Rsh64x(64|32|16|8) (Const64 [0]) _) => (Const64 [0])
430 (Rsh64Ux(64|32|16|8) (Const64 [0]) _) => (Const64 [0])
431 (Lsh32x(64|32|16|8) (Const32 [0]) _) => (Const32 [0])
432 (Rsh32x(64|32|16|8) (Const32 [0]) _) => (Const32 [0])
433 (Rsh32Ux(64|32|16|8) (Const32 [0]) _) => (Const32 [0])
434 (Lsh16x(64|32|16|8) (Const16 [0]) _) => (Const16 [0])
435 (Rsh16x(64|32|16|8) (Const16 [0]) _) => (Const16 [0])
436 (Rsh16Ux(64|32|16|8) (Const16 [0]) _) => (Const16 [0])
437 (Lsh8x(64|32|16|8) (Const8 [0]) _) => (Const8 [0])
438 (Rsh8x(64|32|16|8) (Const8 [0]) _) => (Const8 [0])
439 (Rsh8Ux(64|32|16|8) (Const8 [0]) _) => (Const8 [0])
440
441 // large left shifts of all values, and right shifts of unsigned values
442 ((Lsh64|Rsh64U)x64 _ (Const64 [c])) && uint64(c) >= 64 => (Const64 [0])
443 ((Lsh32|Rsh32U)x64 _ (Const64 [c])) && uint64(c) >= 32 => (Const32 [0])
444 ((Lsh16|Rsh16U)x64 _ (Const64 [c])) && uint64(c) >= 16 => (Const16 [0])
445 ((Lsh8|Rsh8U)x64 _ (Const64 [c])) && uint64(c) >= 8 => (Const8 [0])
446
447 // combine const shifts
448 (Lsh64x64 <t> (Lsh64x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Lsh64x64 x (Const64 <t> [c+d]))
449 (Lsh32x64 <t> (Lsh32x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Lsh32x64 x (Const64 <t> [c+d]))
450 (Lsh16x64 <t> (Lsh16x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Lsh16x64 x (Const64 <t> [c+d]))
451 (Lsh8x64 <t> (Lsh8x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Lsh8x64 x (Const64 <t> [c+d]))
452
453 (Rsh64x64 <t> (Rsh64x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh64x64 x (Const64 <t> [c+d]))
454 (Rsh32x64 <t> (Rsh32x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh32x64 x (Const64 <t> [c+d]))
455 (Rsh16x64 <t> (Rsh16x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh16x64 x (Const64 <t> [c+d]))
456 (Rsh8x64 <t> (Rsh8x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh8x64 x (Const64 <t> [c+d]))
457
458 (Rsh64Ux64 <t> (Rsh64Ux64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh64Ux64 x (Const64 <t> [c+d]))
459 (Rsh32Ux64 <t> (Rsh32Ux64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh32Ux64 x (Const64 <t> [c+d]))
460 (Rsh16Ux64 <t> (Rsh16Ux64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh16Ux64 x (Const64 <t> [c+d]))
461 (Rsh8Ux64 <t> (Rsh8Ux64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh8Ux64 x (Const64 <t> [c+d]))
462
463 // Remove signed right shift before an unsigned right shift that extracts the sign bit.
464 (Rsh8Ux64 (Rsh8x64 x _) (Const64 <t> [7] )) => (Rsh8Ux64 x (Const64 <t> [7] ))
465 (Rsh16Ux64 (Rsh16x64 x _) (Const64 <t> [15])) => (Rsh16Ux64 x (Const64 <t> [15]))
466 (Rsh32Ux64 (Rsh32x64 x _) (Const64 <t> [31])) => (Rsh32Ux64 x (Const64 <t> [31]))
467 (Rsh64Ux64 (Rsh64x64 x _) (Const64 <t> [63])) => (Rsh64Ux64 x (Const64 <t> [63]))
468
469 // Convert x>>c<<c to x&^(1<<c-1)
470 (Lsh64x64 i:(Rsh(64|64U)x64 x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 64 && i.Uses == 1 => (And64 x (Const64 <v.Type> [int64(-1) << c]))
471 (Lsh32x64 i:(Rsh(32|32U)x64 x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 32 && i.Uses == 1 => (And32 x (Const32 <v.Type> [int32(-1) << c]))
472 (Lsh16x64 i:(Rsh(16|16U)x64 x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 16 && i.Uses == 1 => (And16 x (Const16 <v.Type> [int16(-1) << c]))
473 (Lsh8x64 i:(Rsh(8|8U)x64 x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 8 && i.Uses == 1 => (And8 x (Const8 <v.Type> [int8(-1) << c]))
474 // similarly for x<<c>>c
475 (Rsh64Ux64 i:(Lsh64x64 x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 64 && i.Uses == 1 => (And64 x (Const64 <v.Type> [int64(^uint64(0)>>c)]))
476 (Rsh32Ux64 i:(Lsh32x64 x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 32 && i.Uses == 1 => (And32 x (Const32 <v.Type> [int32(^uint32(0)>>c)]))
477 (Rsh16Ux64 i:(Lsh16x64 x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 16 && i.Uses == 1 => (And16 x (Const16 <v.Type> [int16(^uint16(0)>>c)]))
478 (Rsh8Ux64 i:(Lsh8x64 x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 8 && i.Uses == 1 => (And8 x (Const8 <v.Type> [int8 (^uint8 (0)>>c)]))
479
480 // ((x >> c1) << c2) >> c3
481 (Rsh(64|32|16|8)Ux64 (Lsh(64|32|16|8)x64 (Rsh(64|32|16|8)Ux64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3]))
482 && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3)
483 => (Rsh(64|32|16|8)Ux64 x (Const64 <typ.UInt64> [c1-c2+c3]))
484
485 // ((x << c1) >> c2) << c3
486 (Lsh(64|32|16|8)x64 (Rsh(64|32|16|8)Ux64 (Lsh(64|32|16|8)x64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3]))
487 && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3)
488 => (Lsh(64|32|16|8)x64 x (Const64 <typ.UInt64> [c1-c2+c3]))
489
490 // (x >> c) & uppermask = 0
491 (And64 (Const64 [m]) (Rsh64Ux64 _ (Const64 [c]))) && c >= int64(64-ntz64(m)) => (Const64 [0])
492 (And32 (Const32 [m]) (Rsh32Ux64 _ (Const64 [c]))) && c >= int64(32-ntz32(m)) => (Const32 [0])
493 (And16 (Const16 [m]) (Rsh16Ux64 _ (Const64 [c]))) && c >= int64(16-ntz16(m)) => (Const16 [0])
494 (And8 (Const8 [m]) (Rsh8Ux64 _ (Const64 [c]))) && c >= int64(8-ntz8(m)) => (Const8 [0])
495
496 // (x << c) & lowermask = 0
497 (And64 (Const64 [m]) (Lsh64x64 _ (Const64 [c]))) && c >= int64(64-nlz64(m)) => (Const64 [0])
498 (And32 (Const32 [m]) (Lsh32x64 _ (Const64 [c]))) && c >= int64(32-nlz32(m)) => (Const32 [0])
499 (And16 (Const16 [m]) (Lsh16x64 _ (Const64 [c]))) && c >= int64(16-nlz16(m)) => (Const16 [0])
500 (And8 (Const8 [m]) (Lsh8x64 _ (Const64 [c]))) && c >= int64(8-nlz8(m)) => (Const8 [0])
501
502 // replace shifts with zero extensions
503 (Rsh16Ux64 (Lsh16x64 x (Const64 [8])) (Const64 [8])) => (ZeroExt8to16 (Trunc16to8 <typ.UInt8> x))
504 (Rsh32Ux64 (Lsh32x64 x (Const64 [24])) (Const64 [24])) => (ZeroExt8to32 (Trunc32to8 <typ.UInt8> x))
505 (Rsh64Ux64 (Lsh64x64 x (Const64 [56])) (Const64 [56])) => (ZeroExt8to64 (Trunc64to8 <typ.UInt8> x))
506 (Rsh32Ux64 (Lsh32x64 x (Const64 [16])) (Const64 [16])) => (ZeroExt16to32 (Trunc32to16 <typ.UInt16> x))
507 (Rsh64Ux64 (Lsh64x64 x (Const64 [48])) (Const64 [48])) => (ZeroExt16to64 (Trunc64to16 <typ.UInt16> x))
508 (Rsh64Ux64 (Lsh64x64 x (Const64 [32])) (Const64 [32])) => (ZeroExt32to64 (Trunc64to32 <typ.UInt32> x))
509
510 // replace shifts with sign extensions
511 (Rsh16x64 (Lsh16x64 x (Const64 [8])) (Const64 [8])) => (SignExt8to16 (Trunc16to8 <typ.Int8> x))
512 (Rsh32x64 (Lsh32x64 x (Const64 [24])) (Const64 [24])) => (SignExt8to32 (Trunc32to8 <typ.Int8> x))
513 (Rsh64x64 (Lsh64x64 x (Const64 [56])) (Const64 [56])) => (SignExt8to64 (Trunc64to8 <typ.Int8> x))
514 (Rsh32x64 (Lsh32x64 x (Const64 [16])) (Const64 [16])) => (SignExt16to32 (Trunc32to16 <typ.Int16> x))
515 (Rsh64x64 (Lsh64x64 x (Const64 [48])) (Const64 [48])) => (SignExt16to64 (Trunc64to16 <typ.Int16> x))
516 (Rsh64x64 (Lsh64x64 x (Const64 [32])) (Const64 [32])) => (SignExt32to64 (Trunc64to32 <typ.Int32> x))
517
518 // ((x >> c) & d) << e
519 (Lsh64x64 (And64 (Rsh(64|64U)x64 <t> x (Const64 <t2> [c])) (Const64 [d])) (Const64 [e])) && c >= e => (And64 (Rsh(64|64U)x64 <t> x (Const64 <t2> [c-e])) (Const64 <t> [d<<e]))
520 (Lsh32x64 (And32 (Rsh(32|32U)x64 <t> x (Const64 <t2> [c])) (Const32 [d])) (Const64 [e])) && c >= e => (And32 (Rsh(32|32U)x64 <t> x (Const64 <t2> [c-e])) (Const32 <t> [d<<e]))
521 (Lsh16x64 (And16 (Rsh(16|16U)x64 <t> x (Const64 <t2> [c])) (Const16 [d])) (Const64 [e])) && c >= e => (And16 (Rsh(16|16U)x64 <t> x (Const64 <t2> [c-e])) (Const16 <t> [d<<e]))
522 (Lsh8x64 (And8 (Rsh(8|8U)x64 <t> x (Const64 <t2> [c])) (Const8 [d])) (Const64 [e])) && c >= e => (And8 (Rsh(8|8U)x64 <t> x (Const64 <t2> [c-e])) (Const8 <t> [d<<e]))
523 (Lsh64x64 (And64 (Rsh(64|64U)x64 <t> x (Const64 <t2> [c])) (Const64 [d])) (Const64 [e])) && c < e => (And64 (Lsh64x64 <t> x (Const64 <t2> [e-c])) (Const64 <t> [d<<e]))
524 (Lsh32x64 (And32 (Rsh(32|32U)x64 <t> x (Const64 <t2> [c])) (Const32 [d])) (Const64 [e])) && c < e => (And32 (Lsh32x64 <t> x (Const64 <t2> [e-c])) (Const32 <t> [d<<e]))
525 (Lsh16x64 (And16 (Rsh(16|16U)x64 <t> x (Const64 <t2> [c])) (Const16 [d])) (Const64 [e])) && c < e => (And16 (Lsh16x64 <t> x (Const64 <t2> [e-c])) (Const16 <t> [d<<e]))
526 (Lsh8x64 (And8 (Rsh(8|8U)x64 <t> x (Const64 <t2> [c])) (Const8 [d])) (Const64 [e])) && c < e => (And8 (Lsh8x64 <t> x (Const64 <t2> [e-c])) (Const8 <t> [d<<e]))
527
528 // constant comparisons
529 (Eq(64|32|16|8) (Const(64|32|16|8) [c]) (Const(64|32|16|8) [d])) => (ConstBool [c == d])
530 (Neq(64|32|16|8) (Const(64|32|16|8) [c]) (Const(64|32|16|8) [d])) => (ConstBool [c != d])
531 (Less(64|32|16|8) (Const(64|32|16|8) [c]) (Const(64|32|16|8) [d])) => (ConstBool [c < d])
532 (Leq(64|32|16|8) (Const(64|32|16|8) [c]) (Const(64|32|16|8) [d])) => (ConstBool [c <= d])
533
534 (Less64U (Const64 [c]) (Const64 [d])) => (ConstBool [uint64(c) < uint64(d)])
535 (Less32U (Const32 [c]) (Const32 [d])) => (ConstBool [uint32(c) < uint32(d)])
536 (Less16U (Const16 [c]) (Const16 [d])) => (ConstBool [uint16(c) < uint16(d)])
537 (Less8U (Const8 [c]) (Const8 [d])) => (ConstBool [ uint8(c) < uint8(d)])
538
539 (Leq64U (Const64 [c]) (Const64 [d])) => (ConstBool [uint64(c) <= uint64(d)])
540 (Leq32U (Const32 [c]) (Const32 [d])) => (ConstBool [uint32(c) <= uint32(d)])
541 (Leq16U (Const16 [c]) (Const16 [d])) => (ConstBool [uint16(c) <= uint16(d)])
542 (Leq8U (Const8 [c]) (Const8 [d])) => (ConstBool [ uint8(c) <= uint8(d)])
543
544 (Leq8 (Const8 [0]) (And8 _ (Const8 [c]))) && c >= 0 => (ConstBool [true])
545 (Leq16 (Const16 [0]) (And16 _ (Const16 [c]))) && c >= 0 => (ConstBool [true])
546 (Leq32 (Const32 [0]) (And32 _ (Const32 [c]))) && c >= 0 => (ConstBool [true])
547 (Leq64 (Const64 [0]) (And64 _ (Const64 [c]))) && c >= 0 => (ConstBool [true])
548
549 (Leq8 (Const8 [0]) (Rsh8Ux64 _ (Const64 [c]))) && c > 0 => (ConstBool [true])
550 (Leq16 (Const16 [0]) (Rsh16Ux64 _ (Const64 [c]))) && c > 0 => (ConstBool [true])
551 (Leq32 (Const32 [0]) (Rsh32Ux64 _ (Const64 [c]))) && c > 0 => (ConstBool [true])
552 (Leq64 (Const64 [0]) (Rsh64Ux64 _ (Const64 [c]))) && c > 0 => (ConstBool [true])
553
554 // prefer equalities with zero
555 (Less(64|32|16|8) (Const(64|32|16|8) <t> [0]) x) && isNonNegative(x) => (Neq(64|32|16|8) (Const(64|32|16|8) <t> [0]) x)
556 (Less(64|32|16|8) x (Const(64|32|16|8) <t> [1])) && isNonNegative(x) => (Eq(64|32|16|8) (Const(64|32|16|8) <t> [0]) x)
557 (Less(64|32|16|8)U x (Const(64|32|16|8) <t> [1])) => (Eq(64|32|16|8) (Const(64|32|16|8) <t> [0]) x)
558 (Leq(64|32|16|8)U (Const(64|32|16|8) <t> [1]) x) => (Neq(64|32|16|8) (Const(64|32|16|8) <t> [0]) x)
559
560 // prefer comparisons with zero
561 (Less(64|32|16|8) x (Const(64|32|16|8) <t> [1])) => (Leq(64|32|16|8) x (Const(64|32|16|8) <t> [0]))
562 (Leq(64|32|16|8) x (Const(64|32|16|8) <t> [-1])) => (Less(64|32|16|8) x (Const(64|32|16|8) <t> [0]))
563 (Leq(64|32|16|8) (Const(64|32|16|8) <t> [1]) x) => (Less(64|32|16|8) (Const(64|32|16|8) <t> [0]) x)
564 (Less(64|32|16|8) (Const(64|32|16|8) <t> [-1]) x) => (Leq(64|32|16|8) (Const(64|32|16|8) <t> [0]) x)
565
566 // constant floating point comparisons
567 (Eq32F (Const32F [c]) (Const32F [d])) => (ConstBool [c == d])
568 (Eq64F (Const64F [c]) (Const64F [d])) => (ConstBool [c == d])
569 (Neq32F (Const32F [c]) (Const32F [d])) => (ConstBool [c != d])
570 (Neq64F (Const64F [c]) (Const64F [d])) => (ConstBool [c != d])
571 (Less32F (Const32F [c]) (Const32F [d])) => (ConstBool [c < d])
572 (Less64F (Const64F [c]) (Const64F [d])) => (ConstBool [c < d])
573 (Leq32F (Const32F [c]) (Const32F [d])) => (ConstBool [c <= d])
574 (Leq64F (Const64F [c]) (Const64F [d])) => (ConstBool [c <= d])
575
576 // simplifications
577 (Or(64|32|16|8) x x) => x
578 (Or(64|32|16|8) (Const(64|32|16|8) [0]) x) => x
579 (Or(64|32|16|8) (Const(64|32|16|8) [-1]) _) => (Const(64|32|16|8) [-1])
580 (Or(64|32|16|8) (Com(64|32|16|8) x) x) => (Const(64|32|16|8) [-1])
581
582 (And(64|32|16|8) x x) => x
583 (And(64|32|16|8) (Const(64|32|16|8) [-1]) x) => x
584 (And(64|32|16|8) (Const(64|32|16|8) [0]) _) => (Const(64|32|16|8) [0])
585 (And(64|32|16|8) (Com(64|32|16|8) x) x) => (Const(64|32|16|8) [0])
586
587 (Xor(64|32|16|8) x x) => (Const(64|32|16|8) [0])
588 (Xor(64|32|16|8) (Const(64|32|16|8) [0]) x) => x
589 (Xor(64|32|16|8) (Com(64|32|16|8) x) x) => (Const(64|32|16|8) [-1])
590
591 (Add(64|32|16|8) (Const(64|32|16|8) [0]) x) => x
592 (Sub(64|32|16|8) x x) => (Const(64|32|16|8) [0])
593 (Mul(64|32|16|8) (Const(64|32|16|8) [0]) _) => (Const(64|32|16|8) [0])
594 (Mul(64|32)uover <t> (Const(64|32) [0]) x) => (MakeTuple (Const(64|32) <t.FieldType(0)> [0]) (ConstBool <t.FieldType(1)> [false]))
595
596 (Com(64|32|16|8) (Com(64|32|16|8) x)) => x
597 (Com(64|32|16|8) (Const(64|32|16|8) [c])) => (Const(64|32|16|8) [^c])
598
599 (Neg(64|32|16|8) (Sub(64|32|16|8) x y)) => (Sub(64|32|16|8) y x)
600 (Add(64|32|16|8) x (Neg(64|32|16|8) y)) => (Sub(64|32|16|8) x y)
601
602 (Xor(64|32|16|8) (Const(64|32|16|8) [-1]) x) => (Com(64|32|16|8) x)
603
604 (Sub(64|32|16|8) (Neg(64|32|16|8) x) (Com(64|32|16|8) x)) => (Const(64|32|16|8) [1])
605 (Sub(64|32|16|8) (Com(64|32|16|8) x) (Neg(64|32|16|8) x)) => (Const(64|32|16|8) [-1])
606 (Add(64|32|16|8) (Com(64|32|16|8) x) x) => (Const(64|32|16|8) [-1])
607
608 // Simplification when involving common integer
609 // (t + x) - (t + y) == x - y
610 // (t + x) - (y + t) == x - y
611 // (x + t) - (y + t) == x - y
612 // (x + t) - (t + y) == x - y
613 // (x - t) + (t + y) == x + y
614 // (x - t) + (y + t) == x + y
615 (Sub(64|32|16|8) (Add(64|32|16|8) t x) (Add(64|32|16|8) t y)) => (Sub(64|32|16|8) x y)
616 (Add(64|32|16|8) (Sub(64|32|16|8) x t) (Add(64|32|16|8) t y)) => (Add(64|32|16|8) x y)
617
618 // ^(x-1) == ^x+1 == -x
619 (Add(64|32|16|8) (Const(64|32|16|8) [1]) (Com(64|32|16|8) x)) => (Neg(64|32|16|8) x)
620 (Com(64|32|16|8) (Add(64|32|16|8) (Const(64|32|16|8) [-1]) x)) => (Neg(64|32|16|8) x)
621
622 // -(-x) == x
623 (Neg(64|32|16|8) (Neg(64|32|16|8) x)) => x
624
625 // -^x == x+1
626 (Neg(64|32|16|8) <t> (Com(64|32|16|8) x)) => (Add(64|32|16|8) (Const(64|32|16|8) <t> [1]) x)
627
628 (And(64|32|16|8) x (And(64|32|16|8) x y)) => (And(64|32|16|8) x y)
629 (Or(64|32|16|8) x (Or(64|32|16|8) x y)) => (Or(64|32|16|8) x y)
630 (Xor(64|32|16|8) x (Xor(64|32|16|8) x y)) => y
631
632 // Fold comparisons with numeric bounds
633 (Less(64|32|16|8)U _ (Const(64|32|16|8) [0])) => (ConstBool [false])
634 (Leq(64|32|16|8)U (Const(64|32|16|8) [0]) _) => (ConstBool [true])
635 (Less(64|32|16|8)U (Const(64|32|16|8) [-1]) _) => (ConstBool [false])
636 (Leq(64|32|16|8)U _ (Const(64|32|16|8) [-1])) => (ConstBool [true])
637 (Less64 _ (Const64 [math.MinInt64])) => (ConstBool [false])
638 (Less32 _ (Const32 [math.MinInt32])) => (ConstBool [false])
639 (Less16 _ (Const16 [math.MinInt16])) => (ConstBool [false])
640 (Less8 _ (Const8 [math.MinInt8 ])) => (ConstBool [false])
641 (Leq64 (Const64 [math.MinInt64]) _) => (ConstBool [true])
642 (Leq32 (Const32 [math.MinInt32]) _) => (ConstBool [true])
643 (Leq16 (Const16 [math.MinInt16]) _) => (ConstBool [true])
644 (Leq8 (Const8 [math.MinInt8 ]) _) => (ConstBool [true])
645 (Less64 (Const64 [math.MaxInt64]) _) => (ConstBool [false])
646 (Less32 (Const32 [math.MaxInt32]) _) => (ConstBool [false])
647 (Less16 (Const16 [math.MaxInt16]) _) => (ConstBool [false])
648 (Less8 (Const8 [math.MaxInt8 ]) _) => (ConstBool [false])
649 (Leq64 _ (Const64 [math.MaxInt64])) => (ConstBool [true])
650 (Leq32 _ (Const32 [math.MaxInt32])) => (ConstBool [true])
651 (Leq16 _ (Const16 [math.MaxInt16])) => (ConstBool [true])
652 (Leq8 _ (Const8 [math.MaxInt8 ])) => (ConstBool [true])
653
654 // Canonicalize <= on numeric bounds and < near numeric bounds to ==
655 (Leq(64|32|16|8)U x c:(Const(64|32|16|8) [0])) => (Eq(64|32|16|8) x c)
656 (Leq(64|32|16|8)U c:(Const(64|32|16|8) [-1]) x) => (Eq(64|32|16|8) x c)
657 (Less(64|32|16|8)U x (Const(64|32|16|8) <t> [1])) => (Eq(64|32|16|8) x (Const(64|32|16|8) <t> [0]))
658 (Less(64|32|16|8)U (Const(64|32|16|8) <t> [-2]) x) => (Eq(64|32|16|8) x (Const(64|32|16|8) <t> [-1]))
659 (Leq64 x c:(Const64 [math.MinInt64])) => (Eq64 x c)
660 (Leq32 x c:(Const32 [math.MinInt32])) => (Eq32 x c)
661 (Leq16 x c:(Const16 [math.MinInt16])) => (Eq16 x c)
662 (Leq8 x c:(Const8 [math.MinInt8 ])) => (Eq8 x c)
663 (Leq64 c:(Const64 [math.MaxInt64]) x) => (Eq64 x c)
664 (Leq32 c:(Const32 [math.MaxInt32]) x) => (Eq32 x c)
665 (Leq16 c:(Const16 [math.MaxInt16]) x) => (Eq16 x c)
666 (Leq8 c:(Const8 [math.MaxInt8 ]) x) => (Eq8 x c)
667 (Less64 x (Const64 <t> [math.MinInt64+1])) => (Eq64 x (Const64 <t> [math.MinInt64]))
668 (Less32 x (Const32 <t> [math.MinInt32+1])) => (Eq32 x (Const32 <t> [math.MinInt32]))
669 (Less16 x (Const16 <t> [math.MinInt16+1])) => (Eq16 x (Const16 <t> [math.MinInt16]))
670 (Less8 x (Const8 <t> [math.MinInt8 +1])) => (Eq8 x (Const8 <t> [math.MinInt8 ]))
671 (Less64 (Const64 <t> [math.MaxInt64-1]) x) => (Eq64 x (Const64 <t> [math.MaxInt64]))
672 (Less32 (Const32 <t> [math.MaxInt32-1]) x) => (Eq32 x (Const32 <t> [math.MaxInt32]))
673 (Less16 (Const16 <t> [math.MaxInt16-1]) x) => (Eq16 x (Const16 <t> [math.MaxInt16]))
674 (Less8 (Const8 <t> [math.MaxInt8 -1]) x) => (Eq8 x (Const8 <t> [math.MaxInt8 ]))
675
676 // Ands clear bits. Ors set bits.
677 // If a subsequent Or will set all the bits
678 // that an And cleared, we can skip the And.
679 // This happens in bitmasking code like:
680 // x &^= 3 << shift // clear two old bits
681 // x |= v << shift // set two new bits
682 // when shift is a small constant and v ends up a constant 3.
683 (Or8 (And8 x (Const8 [c2])) (Const8 <t> [c1])) && ^(c1 | c2) == 0 => (Or8 (Const8 <t> [c1]) x)
684 (Or16 (And16 x (Const16 [c2])) (Const16 <t> [c1])) && ^(c1 | c2) == 0 => (Or16 (Const16 <t> [c1]) x)
685 (Or32 (And32 x (Const32 [c2])) (Const32 <t> [c1])) && ^(c1 | c2) == 0 => (Or32 (Const32 <t> [c1]) x)
686 (Or64 (And64 x (Const64 [c2])) (Const64 <t> [c1])) && ^(c1 | c2) == 0 => (Or64 (Const64 <t> [c1]) x)
687
688 (Trunc64to8 (And64 (Const64 [y]) x)) && y&0xFF == 0xFF => (Trunc64to8 x)
689 (Trunc64to16 (And64 (Const64 [y]) x)) && y&0xFFFF == 0xFFFF => (Trunc64to16 x)
690 (Trunc64to32 (And64 (Const64 [y]) x)) && y&0xFFFFFFFF == 0xFFFFFFFF => (Trunc64to32 x)
691 (Trunc32to8 (And32 (Const32 [y]) x)) && y&0xFF == 0xFF => (Trunc32to8 x)
692 (Trunc32to16 (And32 (Const32 [y]) x)) && y&0xFFFF == 0xFFFF => (Trunc32to16 x)
693 (Trunc16to8 (And16 (Const16 [y]) x)) && y&0xFF == 0xFF => (Trunc16to8 x)
694
695 (ZeroExt8to64 (Trunc64to8 x:(Rsh64Ux64 _ (Const64 [s])))) && s >= 56 => x
696 (ZeroExt16to64 (Trunc64to16 x:(Rsh64Ux64 _ (Const64 [s])))) && s >= 48 => x
697 (ZeroExt32to64 (Trunc64to32 x:(Rsh64Ux64 _ (Const64 [s])))) && s >= 32 => x
698 (ZeroExt8to32 (Trunc32to8 x:(Rsh32Ux64 _ (Const64 [s])))) && s >= 24 => x
699 (ZeroExt16to32 (Trunc32to16 x:(Rsh32Ux64 _ (Const64 [s])))) && s >= 16 => x
700 (ZeroExt8to16 (Trunc16to8 x:(Rsh16Ux64 _ (Const64 [s])))) && s >= 8 => x
701
702 (SignExt8to64 (Trunc64to8 x:(Rsh64x64 _ (Const64 [s])))) && s >= 56 => x
703 (SignExt16to64 (Trunc64to16 x:(Rsh64x64 _ (Const64 [s])))) && s >= 48 => x
704 (SignExt32to64 (Trunc64to32 x:(Rsh64x64 _ (Const64 [s])))) && s >= 32 => x
705 (SignExt8to32 (Trunc32to8 x:(Rsh32x64 _ (Const64 [s])))) && s >= 24 => x
706 (SignExt16to32 (Trunc32to16 x:(Rsh32x64 _ (Const64 [s])))) && s >= 16 => x
707 (SignExt8to16 (Trunc16to8 x:(Rsh16x64 _ (Const64 [s])))) && s >= 8 => x
708
709 (Slicemask (Const32 [x])) && x > 0 => (Const32 [-1])
710 (Slicemask (Const32 [0])) => (Const32 [0])
711 (Slicemask (Const64 [x])) && x > 0 => (Const64 [-1])
712 (Slicemask (Const64 [0])) => (Const64 [0])
713
714 // simplifications often used for lengths. e.g. len(s[i:i+5])==5
715 (Sub(64|32|16|8) (Add(64|32|16|8) x y) x) => y
716 (Sub(64|32|16|8) (Add(64|32|16|8) x y) y) => x
717 (Sub(64|32|16|8) (Sub(64|32|16|8) x y) x) => (Neg(64|32|16|8) y)
718 (Sub(64|32|16|8) x (Add(64|32|16|8) x y)) => (Neg(64|32|16|8) y)
719 (Add(64|32|16|8) x (Sub(64|32|16|8) y x)) => y
720 (Add(64|32|16|8) x (Add(64|32|16|8) y (Sub(64|32|16|8) z x))) => (Add(64|32|16|8) y z)
721
722 // basic phi simplifications
723 (Phi (Const8 [c]) (Const8 [c])) => (Const8 [c])
724 (Phi (Const16 [c]) (Const16 [c])) => (Const16 [c])
725 (Phi (Const32 [c]) (Const32 [c])) => (Const32 [c])
726 (Phi (Const64 [c]) (Const64 [c])) => (Const64 [c])
727
728 // slice and interface comparisons
729 // The frontend ensures that we can only compare against nil,
730 // so we need only compare the first word (interface type or slice ptr).
731 (EqInter x y) => (EqPtr (ITab x) (ITab y))
732 (NeqInter x y) => (NeqPtr (ITab x) (ITab y))
733 (EqSlice x y) => (EqPtr (SlicePtr x) (SlicePtr y))
734 (NeqSlice x y) => (NeqPtr (SlicePtr x) (SlicePtr y))
735
736 // Load of store of same address, with compatibly typed value and same size
737 (Load <t1> p1 (Store {t2} p2 x _))
738 && isSamePtr(p1, p2)
739 && copyCompatibleType(t1, x.Type)
740 && t1.Size() == t2.Size()
741 => x
742 (Load <t1> p1 (Store {t2} p2 _ (Store {t3} p3 x _)))
743 && isSamePtr(p1, p3)
744 && copyCompatibleType(t1, x.Type)
745 && t1.Size() == t3.Size()
746 && disjoint(p3, t3.Size(), p2, t2.Size())
747 => x
748 (Load <t1> p1 (Store {t2} p2 _ (Store {t3} p3 _ (Store {t4} p4 x _))))
749 && isSamePtr(p1, p4)
750 && copyCompatibleType(t1, x.Type)
751 && t1.Size() == t4.Size()
752 && disjoint(p4, t4.Size(), p2, t2.Size())
753 && disjoint(p4, t4.Size(), p3, t3.Size())
754 => x
755 (Load <t1> p1 (Store {t2} p2 _ (Store {t3} p3 _ (Store {t4} p4 _ (Store {t5} p5 x _)))))
756 && isSamePtr(p1, p5)
757 && copyCompatibleType(t1, x.Type)
758 && t1.Size() == t5.Size()
759 && disjoint(p5, t5.Size(), p2, t2.Size())
760 && disjoint(p5, t5.Size(), p3, t3.Size())
761 && disjoint(p5, t5.Size(), p4, t4.Size())
762 => x
763
764 // Pass constants through math.Float{32,64}bits and math.Float{32,64}frombits
765 (Load <t1> p1 (Store {t2} p2 (Const64 [x]) _)) && isSamePtr(p1,p2) && t2.Size() == 8 && is64BitFloat(t1) && !math.IsNaN(math.Float64frombits(uint64(x))) => (Const64F [math.Float64frombits(uint64(x))])
766 (Load <t1> p1 (Store {t2} p2 (Const32 [x]) _)) && isSamePtr(p1,p2) && t2.Size() == 4 && is32BitFloat(t1) && !math.IsNaN(float64(math.Float32frombits(uint32(x)))) => (Const32F [math.Float32frombits(uint32(x))])
767 (Load <t1> p1 (Store {t2} p2 (Const64F [x]) _)) && isSamePtr(p1,p2) && t2.Size() == 8 && is64BitInt(t1) => (Const64 [int64(math.Float64bits(x))])
768 (Load <t1> p1 (Store {t2} p2 (Const32F [x]) _)) && isSamePtr(p1,p2) && t2.Size() == 4 && is32BitInt(t1) => (Const32 [int32(math.Float32bits(x))])
769
770 // Float Loads up to Zeros so they can be constant folded.
771 (Load <t1> op:(OffPtr [o1] p1)
772 (Store {t2} p2 _
773 mem:(Zero [n] p3 _)))
774 && o1 >= 0 && o1+t1.Size() <= n && isSamePtr(p1, p3)
775 && CanSSA(t1)
776 && disjoint(op, t1.Size(), p2, t2.Size())
777 => @mem.Block (Load <t1> (OffPtr <op.Type> [o1] p3) mem)
778 (Load <t1> op:(OffPtr [o1] p1)
779 (Store {t2} p2 _
780 (Store {t3} p3 _
781 mem:(Zero [n] p4 _))))
782 && o1 >= 0 && o1+t1.Size() <= n && isSamePtr(p1, p4)
783 && CanSSA(t1)
784 && disjoint(op, t1.Size(), p2, t2.Size())
785 && disjoint(op, t1.Size(), p3, t3.Size())
786 => @mem.Block (Load <t1> (OffPtr <op.Type> [o1] p4) mem)
787 (Load <t1> op:(OffPtr [o1] p1)
788 (Store {t2} p2 _
789 (Store {t3} p3 _
790 (Store {t4} p4 _
791 mem:(Zero [n] p5 _)))))
792 && o1 >= 0 && o1+t1.Size() <= n && isSamePtr(p1, p5)
793 && CanSSA(t1)
794 && disjoint(op, t1.Size(), p2, t2.Size())
795 && disjoint(op, t1.Size(), p3, t3.Size())
796 && disjoint(op, t1.Size(), p4, t4.Size())
797 => @mem.Block (Load <t1> (OffPtr <op.Type> [o1] p5) mem)
798 (Load <t1> op:(OffPtr [o1] p1)
799 (Store {t2} p2 _
800 (Store {t3} p3 _
801 (Store {t4} p4 _
802 (Store {t5} p5 _
803 mem:(Zero [n] p6 _))))))
804 && o1 >= 0 && o1+t1.Size() <= n && isSamePtr(p1, p6)
805 && CanSSA(t1)
806 && disjoint(op, t1.Size(), p2, t2.Size())
807 && disjoint(op, t1.Size(), p3, t3.Size())
808 && disjoint(op, t1.Size(), p4, t4.Size())
809 && disjoint(op, t1.Size(), p5, t5.Size())
810 => @mem.Block (Load <t1> (OffPtr <op.Type> [o1] p6) mem)
811
812 // Zero to Load forwarding.
813 (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
814 && t1.IsBoolean()
815 && isSamePtr(p1, p2)
816 && n >= o + 1
817 => (ConstBool [false])
818 (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
819 && is8BitInt(t1)
820 && isSamePtr(p1, p2)
821 && n >= o + 1
822 => (Const8 [0])
823 (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
824 && is16BitInt(t1)
825 && isSamePtr(p1, p2)
826 && n >= o + 2
827 => (Const16 [0])
828 (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
829 && is32BitInt(t1)
830 && isSamePtr(p1, p2)
831 && n >= o + 4
832 => (Const32 [0])
833 (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
834 && is64BitInt(t1)
835 && isSamePtr(p1, p2)
836 && n >= o + 8
837 => (Const64 [0])
838 (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
839 && is32BitFloat(t1)
840 && isSamePtr(p1, p2)
841 && n >= o + 4
842 => (Const32F [0])
843 (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
844 && is64BitFloat(t1)
845 && isSamePtr(p1, p2)
846 && n >= o + 8
847 => (Const64F [0])
848
849 // Eliminate stores of values that have just been loaded from the same location.
850 // We also handle the common case where there are some intermediate stores.
851 (Store {t1} p1 (Load <t2> p2 mem) mem)
852 && isSamePtr(p1, p2)
853 && t2.Size() == t1.Size()
854 => mem
855 (Store {t1} p1 (Load <t2> p2 oldmem) mem:(Store {t3} p3 _ oldmem))
856 && isSamePtr(p1, p2)
857 && t2.Size() == t1.Size()
858 && disjoint(p1, t1.Size(), p3, t3.Size())
859 => mem
860 (Store {t1} p1 (Load <t2> p2 oldmem) mem:(Store {t3} p3 _ (Store {t4} p4 _ oldmem)))
861 && isSamePtr(p1, p2)
862 && t2.Size() == t1.Size()
863 && disjoint(p1, t1.Size(), p3, t3.Size())
864 && disjoint(p1, t1.Size(), p4, t4.Size())
865 => mem
866 (Store {t1} p1 (Load <t2> p2 oldmem) mem:(Store {t3} p3 _ (Store {t4} p4 _ (Store {t5} p5 _ oldmem))))
867 && isSamePtr(p1, p2)
868 && t2.Size() == t1.Size()
869 && disjoint(p1, t1.Size(), p3, t3.Size())
870 && disjoint(p1, t1.Size(), p4, t4.Size())
871 && disjoint(p1, t1.Size(), p5, t5.Size())
872 => mem
873
874 // Don't Store zeros to cleared variables.
875 (Store {t} (OffPtr [o] p1) x mem:(Zero [n] p2 _))
876 && isConstZero(x)
877 && o >= 0 && t.Size() + o <= n && isSamePtr(p1, p2)
878 => mem
879 (Store {t1} op:(OffPtr [o1] p1) x mem:(Store {t2} p2 _ (Zero [n] p3 _)))
880 && isConstZero(x)
881 && o1 >= 0 && t1.Size() + o1 <= n && isSamePtr(p1, p3)
882 && disjoint(op, t1.Size(), p2, t2.Size())
883 => mem
884 (Store {t1} op:(OffPtr [o1] p1) x mem:(Store {t2} p2 _ (Store {t3} p3 _ (Zero [n] p4 _))))
885 && isConstZero(x)
886 && o1 >= 0 && t1.Size() + o1 <= n && isSamePtr(p1, p4)
887 && disjoint(op, t1.Size(), p2, t2.Size())
888 && disjoint(op, t1.Size(), p3, t3.Size())
889 => mem
890 (Store {t1} op:(OffPtr [o1] p1) x mem:(Store {t2} p2 _ (Store {t3} p3 _ (Store {t4} p4 _ (Zero [n] p5 _)))))
891 && isConstZero(x)
892 && o1 >= 0 && t1.Size() + o1 <= n && isSamePtr(p1, p5)
893 && disjoint(op, t1.Size(), p2, t2.Size())
894 && disjoint(op, t1.Size(), p3, t3.Size())
895 && disjoint(op, t1.Size(), p4, t4.Size())
896 => mem
897
898 // Collapse OffPtr
899 (OffPtr (OffPtr p [y]) [x]) => (OffPtr p [x+y])
900 (OffPtr p [0]) && v.Type.Compare(p.Type) == types.CMPeq => p
901
902 // indexing operations
903 // Note: bounds check has already been done
904 (PtrIndex <t> ptr idx) && config.PtrSize == 4 && is32Bit(t.Elem().Size()) => (AddPtr ptr (Mul32 <typ.Int> idx (Const32 <typ.Int> [int32(t.Elem().Size())])))
905 (PtrIndex <t> ptr idx) && config.PtrSize == 8 => (AddPtr ptr (Mul64 <typ.Int> idx (Const64 <typ.Int> [t.Elem().Size()])))
906
907 // struct operations
908 (StructSelect [i] x:(StructMake ___)) => x.Args[i]
909 (Load <t> _ _) && t.IsStruct() && CanSSA(t) => rewriteStructLoad(v)
910 (Store _ (StructMake ___) _) => rewriteStructStore(v)
911
912 (StructSelect [i] x:(Load <t> ptr mem)) && !CanSSA(t) =>
913 @x.Block (Load <v.Type> (OffPtr <v.Type.PtrTo()> [t.FieldOff(int(i))] ptr) mem)
914
915 // Putting struct{*byte} and similar into direct interfaces.
916 (IMake _typ (StructMake val)) => (IMake _typ val)
917 (StructSelect [0] (IData x)) => (IData x)
918
919 // un-SSAable values use mem->mem copies
920 (Store {t} dst (Load src mem) mem) && !CanSSA(t) =>
921 (Move {t} [t.Size()] dst src mem)
922 (Store {t} dst (Load src mem) (VarDef {x} mem)) && !CanSSA(t) =>
923 (Move {t} [t.Size()] dst src (VarDef {x} mem))
924
925 // array ops
926 (ArraySelect (ArrayMake1 x)) => x
927
928 (Load <t> _ _) && t.IsArray() && t.NumElem() == 0 =>
929 (ArrayMake0)
930
931 (Load <t> ptr mem) && t.IsArray() && t.NumElem() == 1 && CanSSA(t) =>
932 (ArrayMake1 (Load <t.Elem()> ptr mem))
933
934 (Store _ (ArrayMake0) mem) => mem
935 (Store dst (ArrayMake1 e) mem) => (Store {e.Type} dst e mem)
936
937 // Putting [1]*byte and similar into direct interfaces.
938 (IMake _typ (ArrayMake1 val)) => (IMake _typ val)
939 (ArraySelect [0] (IData x)) => (IData x)
940
941 // string ops
942 // Decomposing StringMake and lowering of StringPtr and StringLen
943 // happens in a later pass, dec, so that these operations are available
944 // to other passes for optimizations.
945 (StringPtr (StringMake (Addr <t> {s} base) _)) => (Addr <t> {s} base)
946 (StringLen (StringMake _ (Const64 <t> [c]))) => (Const64 <t> [c])
947 (ConstString {str}) && config.PtrSize == 4 && str == "" =>
948 (StringMake (ConstNil) (Const32 <typ.Int> [0]))
949 (ConstString {str}) && config.PtrSize == 8 && str == "" =>
950 (StringMake (ConstNil) (Const64 <typ.Int> [0]))
951 (ConstString {str}) && config.PtrSize == 4 && str != "" =>
952 (StringMake
953 (Addr <typ.BytePtr> {fe.StringData(str)}
954 (SB))
955 (Const32 <typ.Int> [int32(len(str))]))
956 (ConstString {str}) && config.PtrSize == 8 && str != "" =>
957 (StringMake
958 (Addr <typ.BytePtr> {fe.StringData(str)}
959 (SB))
960 (Const64 <typ.Int> [int64(len(str))]))
961
962 // slice ops
963 // Only a few slice rules are provided here. See dec.rules for
964 // a more comprehensive set.
965 (SliceLen (SliceMake _ (Const64 <t> [c]) _)) => (Const64 <t> [c])
966 (SliceCap (SliceMake _ _ (Const64 <t> [c]))) => (Const64 <t> [c])
967 (SliceLen (SliceMake _ (Const32 <t> [c]) _)) => (Const32 <t> [c])
968 (SliceCap (SliceMake _ _ (Const32 <t> [c]))) => (Const32 <t> [c])
969 (SlicePtr (SliceMake (SlicePtr x) _ _)) => (SlicePtr x)
970 (SliceLen (SliceMake _ (SliceLen x) _)) => (SliceLen x)
971 (SliceCap (SliceMake _ _ (SliceCap x))) => (SliceCap x)
972 (SliceCap (SliceMake _ _ (SliceLen x))) => (SliceLen x)
973 (ConstSlice) && config.PtrSize == 4 =>
974 (SliceMake
975 (ConstNil <v.Type.Elem().PtrTo()>)
976 (Const32 <typ.Int> [0])
977 (Const32 <typ.Int> [0]))
978 (ConstSlice) && config.PtrSize == 8 =>
979 (SliceMake
980 (ConstNil <v.Type.Elem().PtrTo()>)
981 (Const64 <typ.Int> [0])
982 (Const64 <typ.Int> [0]))
983
984 // interface ops
985 (ConstInterface) =>
986 (IMake
987 (ConstNil <typ.Uintptr>)
988 (ConstNil <typ.BytePtr>))
989
990 (NilCheck ptr:(GetG mem) mem) => ptr
991
992 (If (Not cond) yes no) => (If cond no yes)
993 (If (ConstBool [c]) yes no) && c => (First yes no)
994 (If (ConstBool [c]) yes no) && !c => (First no yes)
995
996 (Phi <t> nx:(Not x) ny:(Not y)) && nx.Uses == 1 && ny.Uses == 1 => (Not (Phi <t> x y))
997
998 // Get rid of Convert ops for pointer arithmetic on unsafe.Pointer.
999 (Convert (Add(64|32) (Convert ptr mem) off) mem) => (AddPtr ptr off)
1000 (Convert (Convert ptr mem) mem) => ptr
1001 // Note: it is important that the target rewrite is ptr+(off1+off2), not (ptr+off1)+off2.
1002 // We must ensure that no intermediate computations are invalid pointers.
1003 (Convert a:(Add(64|32) (Add(64|32) (Convert ptr mem) off1) off2) mem) => (AddPtr ptr (Add(64|32) <a.Type> off1 off2))
1004
1005 // strength reduction of divide by a constant.
1006 // See ../magic.go for a detailed description of these algorithms.
1007
1008 // Unsigned divide by power of 2. Strength reduce to a shift.
1009 (Div8u n (Const8 [c])) && isPowerOfTwo(c) => (Rsh8Ux64 n (Const64 <typ.UInt64> [log8(c)]))
1010 (Div16u n (Const16 [c])) && isPowerOfTwo(c) => (Rsh16Ux64 n (Const64 <typ.UInt64> [log16(c)]))
1011 (Div32u n (Const32 [c])) && isPowerOfTwo(c) => (Rsh32Ux64 n (Const64 <typ.UInt64> [log32(c)]))
1012 (Div64u n (Const64 [c])) && isPowerOfTwo(c) => (Rsh64Ux64 n (Const64 <typ.UInt64> [log64(c)]))
1013 (Div64u n (Const64 [-1<<63])) => (Rsh64Ux64 n (Const64 <typ.UInt64> [63]))
1014
1015 // Signed non-negative divide by power of 2.
1016 (Div8 n (Const8 [c])) && isNonNegative(n) && isPowerOfTwo(c) => (Rsh8Ux64 n (Const64 <typ.UInt64> [log8(c)]))
1017 (Div16 n (Const16 [c])) && isNonNegative(n) && isPowerOfTwo(c) => (Rsh16Ux64 n (Const64 <typ.UInt64> [log16(c)]))
1018 (Div32 n (Const32 [c])) && isNonNegative(n) && isPowerOfTwo(c) => (Rsh32Ux64 n (Const64 <typ.UInt64> [log32(c)]))
1019 (Div64 n (Const64 [c])) && isNonNegative(n) && isPowerOfTwo(c) => (Rsh64Ux64 n (Const64 <typ.UInt64> [log64(c)]))
1020 (Div64 n (Const64 [-1<<63])) && isNonNegative(n) => (Const64 [0])
1021
1022 // Unsigned divide, not a power of 2. Strength reduce to a multiply.
1023 // For 8-bit divides, we just do a direct 9-bit by 8-bit multiply.
1024 (Div8u x (Const8 [c])) && umagicOK8(c) =>
1025 (Trunc32to8
1026 (Rsh32Ux64 <typ.UInt32>
1027 (Mul32 <typ.UInt32>
1028 (Const32 <typ.UInt32> [int32(1<<8+umagic8(c).m)])
1029 (ZeroExt8to32 x))
1030 (Const64 <typ.UInt64> [8+umagic8(c).s])))
1031
1032 // For 16-bit divides on 64-bit machines, we do a direct 17-bit by 16-bit multiply.
1033 (Div16u x (Const16 [c])) && umagicOK16(c) && config.RegSize == 8 =>
1034 (Trunc64to16
1035 (Rsh64Ux64 <typ.UInt64>
1036 (Mul64 <typ.UInt64>
1037 (Const64 <typ.UInt64> [int64(1<<16+umagic16(c).m)])
1038 (ZeroExt16to64 x))
1039 (Const64 <typ.UInt64> [16+umagic16(c).s])))
1040
1041 // For 16-bit divides on 32-bit machines
1042 (Div16u x (Const16 [c])) && umagicOK16(c) && config.RegSize == 4 && umagic16(c).m&1 == 0 =>
1043 (Trunc32to16
1044 (Rsh32Ux64 <typ.UInt32>
1045 (Mul32 <typ.UInt32>
1046 (Const32 <typ.UInt32> [int32(1<<15+umagic16(c).m/2)])
1047 (ZeroExt16to32 x))
1048 (Const64 <typ.UInt64> [16+umagic16(c).s-1])))
1049 (Div16u x (Const16 [c])) && umagicOK16(c) && config.RegSize == 4 && c&1 == 0 =>
1050 (Trunc32to16
1051 (Rsh32Ux64 <typ.UInt32>
1052 (Mul32 <typ.UInt32>
1053 (Const32 <typ.UInt32> [int32(1<<15+(umagic16(c).m+1)/2)])
1054 (Rsh32Ux64 <typ.UInt32> (ZeroExt16to32 x) (Const64 <typ.UInt64> [1])))
1055 (Const64 <typ.UInt64> [16+umagic16(c).s-2])))
1056 (Div16u x (Const16 [c])) && umagicOK16(c) && config.RegSize == 4 && config.useAvg =>
1057 (Trunc32to16
1058 (Rsh32Ux64 <typ.UInt32>
1059 (Avg32u
1060 (Lsh32x64 <typ.UInt32> (ZeroExt16to32 x) (Const64 <typ.UInt64> [16]))
1061 (Mul32 <typ.UInt32>
1062 (Const32 <typ.UInt32> [int32(umagic16(c).m)])
1063 (ZeroExt16to32 x)))
1064 (Const64 <typ.UInt64> [16+umagic16(c).s-1])))
1065
1066 // For 32-bit divides on 32-bit machines
1067 (Div32u x (Const32 [c])) && umagicOK32(c) && config.RegSize == 4 && umagic32(c).m&1 == 0 && config.useHmul =>
1068 (Rsh32Ux64 <typ.UInt32>
1069 (Hmul32u <typ.UInt32>
1070 (Const32 <typ.UInt32> [int32(1<<31+umagic32(c).m/2)])
1071 x)
1072 (Const64 <typ.UInt64> [umagic32(c).s-1]))
1073 (Div32u x (Const32 [c])) && umagicOK32(c) && config.RegSize == 4 && c&1 == 0 && config.useHmul =>
1074 (Rsh32Ux64 <typ.UInt32>
1075 (Hmul32u <typ.UInt32>
1076 (Const32 <typ.UInt32> [int32(1<<31+(umagic32(c).m+1)/2)])
1077 (Rsh32Ux64 <typ.UInt32> x (Const64 <typ.UInt64> [1])))
1078 (Const64 <typ.UInt64> [umagic32(c).s-2]))
1079 (Div32u x (Const32 [c])) && umagicOK32(c) && config.RegSize == 4 && config.useAvg && config.useHmul =>
1080 (Rsh32Ux64 <typ.UInt32>
1081 (Avg32u
1082 x
1083 (Hmul32u <typ.UInt32>
1084 (Const32 <typ.UInt32> [int32(umagic32(c).m)])
1085 x))
1086 (Const64 <typ.UInt64> [umagic32(c).s-1]))
1087
1088 // For 32-bit divides on 64-bit machines
1089 // We'll use a regular (non-hi) multiply for this case.
1090 (Div32u x (Const32 [c])) && umagicOK32(c) && config.RegSize == 8 && umagic32(c).m&1 == 0 =>
1091 (Trunc64to32
1092 (Rsh64Ux64 <typ.UInt64>
1093 (Mul64 <typ.UInt64>
1094 (Const64 <typ.UInt64> [int64(1<<31+umagic32(c).m/2)])
1095 (ZeroExt32to64 x))
1096 (Const64 <typ.UInt64> [32+umagic32(c).s-1])))
1097 (Div32u x (Const32 [c])) && umagicOK32(c) && config.RegSize == 8 && c&1 == 0 =>
1098 (Trunc64to32
1099 (Rsh64Ux64 <typ.UInt64>
1100 (Mul64 <typ.UInt64>
1101 (Const64 <typ.UInt64> [int64(1<<31+(umagic32(c).m+1)/2)])
1102 (Rsh64Ux64 <typ.UInt64> (ZeroExt32to64 x) (Const64 <typ.UInt64> [1])))
1103 (Const64 <typ.UInt64> [32+umagic32(c).s-2])))
1104 (Div32u x (Const32 [c])) && umagicOK32(c) && config.RegSize == 8 && config.useAvg =>
1105 (Trunc64to32
1106 (Rsh64Ux64 <typ.UInt64>
1107 (Avg64u
1108 (Lsh64x64 <typ.UInt64> (ZeroExt32to64 x) (Const64 <typ.UInt64> [32]))
1109 (Mul64 <typ.UInt64>
1110 (Const64 <typ.UInt32> [int64(umagic32(c).m)])
1111 (ZeroExt32to64 x)))
1112 (Const64 <typ.UInt64> [32+umagic32(c).s-1])))
1113
1114 // For unsigned 64-bit divides on 32-bit machines,
1115 // if the constant fits in 16 bits (so that the last term
1116 // fits in 32 bits), convert to three 32-bit divides by a constant.
1117 //
1118 // If 1<<32 = Q * c + R
1119 // and x = hi << 32 + lo
1120 //
1121 // Then x = (hi/c*c + hi%c) << 32 + lo
1122 // = hi/c*c<<32 + hi%c<<32 + lo
1123 // = hi/c*c<<32 + (hi%c)*(Q*c+R) + lo/c*c + lo%c
1124 // = hi/c*c<<32 + (hi%c)*Q*c + lo/c*c + (hi%c*R+lo%c)
1125 // and x / c = (hi/c)<<32 + (hi%c)*Q + lo/c + (hi%c*R+lo%c)/c
1126 (Div64u x (Const64 [c])) && c > 0 && c <= 0xFFFF && umagicOK32(int32(c)) && config.RegSize == 4 && config.useHmul =>
1127 (Add64
1128 (Add64 <typ.UInt64>
1129 (Add64 <typ.UInt64>
1130 (Lsh64x64 <typ.UInt64>
1131 (ZeroExt32to64
1132 (Div32u <typ.UInt32>
1133 (Trunc64to32 <typ.UInt32> (Rsh64Ux64 <typ.UInt64> x (Const64 <typ.UInt64> [32])))
1134 (Const32 <typ.UInt32> [int32(c)])))
1135 (Const64 <typ.UInt64> [32]))
1136 (ZeroExt32to64 (Div32u <typ.UInt32> (Trunc64to32 <typ.UInt32> x) (Const32 <typ.UInt32> [int32(c)]))))
1137 (Mul64 <typ.UInt64>
1138 (ZeroExt32to64 <typ.UInt64>
1139 (Mod32u <typ.UInt32>
1140 (Trunc64to32 <typ.UInt32> (Rsh64Ux64 <typ.UInt64> x (Const64 <typ.UInt64> [32])))
1141 (Const32 <typ.UInt32> [int32(c)])))
1142 (Const64 <typ.UInt64> [int64((1<<32)/c)])))
1143 (ZeroExt32to64
1144 (Div32u <typ.UInt32>
1145 (Add32 <typ.UInt32>
1146 (Mod32u <typ.UInt32> (Trunc64to32 <typ.UInt32> x) (Const32 <typ.UInt32> [int32(c)]))
1147 (Mul32 <typ.UInt32>
1148 (Mod32u <typ.UInt32>
1149 (Trunc64to32 <typ.UInt32> (Rsh64Ux64 <typ.UInt64> x (Const64 <typ.UInt64> [32])))
1150 (Const32 <typ.UInt32> [int32(c)]))
1151 (Const32 <typ.UInt32> [int32((1<<32)%c)])))
1152 (Const32 <typ.UInt32> [int32(c)]))))
1153
1154 // For 64-bit divides on 64-bit machines
1155 // (64-bit divides on 32-bit machines are lowered to a runtime call by the walk pass.)
1156 (Div64u x (Const64 [c])) && umagicOK64(c) && config.RegSize == 8 && umagic64(c).m&1 == 0 && config.useHmul =>
1157 (Rsh64Ux64 <typ.UInt64>
1158 (Hmul64u <typ.UInt64>
1159 (Const64 <typ.UInt64> [int64(1<<63+umagic64(c).m/2)])
1160 x)
1161 (Const64 <typ.UInt64> [umagic64(c).s-1]))
1162 (Div64u x (Const64 [c])) && umagicOK64(c) && config.RegSize == 8 && c&1 == 0 && config.useHmul =>
1163 (Rsh64Ux64 <typ.UInt64>
1164 (Hmul64u <typ.UInt64>
1165 (Const64 <typ.UInt64> [int64(1<<63+(umagic64(c).m+1)/2)])
1166 (Rsh64Ux64 <typ.UInt64> x (Const64 <typ.UInt64> [1])))
1167 (Const64 <typ.UInt64> [umagic64(c).s-2]))
1168 (Div64u x (Const64 [c])) && umagicOK64(c) && config.RegSize == 8 && config.useAvg && config.useHmul =>
1169 (Rsh64Ux64 <typ.UInt64>
1170 (Avg64u
1171 x
1172 (Hmul64u <typ.UInt64>
1173 (Const64 <typ.UInt64> [int64(umagic64(c).m)])
1174 x))
1175 (Const64 <typ.UInt64> [umagic64(c).s-1]))
1176
1177 // Signed divide by a negative constant. Rewrite to divide by a positive constant.
1178 (Div8 <t> n (Const8 [c])) && c < 0 && c != -1<<7 => (Neg8 (Div8 <t> n (Const8 <t> [-c])))
1179 (Div16 <t> n (Const16 [c])) && c < 0 && c != -1<<15 => (Neg16 (Div16 <t> n (Const16 <t> [-c])))
1180 (Div32 <t> n (Const32 [c])) && c < 0 && c != -1<<31 => (Neg32 (Div32 <t> n (Const32 <t> [-c])))
1181 (Div64 <t> n (Const64 [c])) && c < 0 && c != -1<<63 => (Neg64 (Div64 <t> n (Const64 <t> [-c])))
1182
1183 // Dividing by the most-negative number. Result is always 0 except
1184 // if the input is also the most-negative number.
1185 // We can detect that using the sign bit of x & -x.
1186 (Div8 <t> x (Const8 [-1<<7 ])) => (Rsh8Ux64 (And8 <t> x (Neg8 <t> x)) (Const64 <typ.UInt64> [7 ]))
1187 (Div16 <t> x (Const16 [-1<<15])) => (Rsh16Ux64 (And16 <t> x (Neg16 <t> x)) (Const64 <typ.UInt64> [15]))
1188 (Div32 <t> x (Const32 [-1<<31])) => (Rsh32Ux64 (And32 <t> x (Neg32 <t> x)) (Const64 <typ.UInt64> [31]))
1189 (Div64 <t> x (Const64 [-1<<63])) => (Rsh64Ux64 (And64 <t> x (Neg64 <t> x)) (Const64 <typ.UInt64> [63]))
1190
1191 // Signed divide by power of 2.
1192 // n / c = n >> log(c) if n >= 0
1193 // = (n+c-1) >> log(c) if n < 0
1194 // We conditionally add c-1 by adding n>>63>>(64-log(c)) (first shift signed, second shift unsigned).
1195 (Div8 <t> n (Const8 [c])) && isPowerOfTwo(c) =>
1196 (Rsh8x64
1197 (Add8 <t> n (Rsh8Ux64 <t> (Rsh8x64 <t> n (Const64 <typ.UInt64> [ 7])) (Const64 <typ.UInt64> [int64( 8-log8(c))])))
1198 (Const64 <typ.UInt64> [int64(log8(c))]))
1199 (Div16 <t> n (Const16 [c])) && isPowerOfTwo(c) =>
1200 (Rsh16x64
1201 (Add16 <t> n (Rsh16Ux64 <t> (Rsh16x64 <t> n (Const64 <typ.UInt64> [15])) (Const64 <typ.UInt64> [int64(16-log16(c))])))
1202 (Const64 <typ.UInt64> [int64(log16(c))]))
1203 (Div32 <t> n (Const32 [c])) && isPowerOfTwo(c) =>
1204 (Rsh32x64
1205 (Add32 <t> n (Rsh32Ux64 <t> (Rsh32x64 <t> n (Const64 <typ.UInt64> [31])) (Const64 <typ.UInt64> [int64(32-log32(c))])))
1206 (Const64 <typ.UInt64> [int64(log32(c))]))
1207 (Div64 <t> n (Const64 [c])) && isPowerOfTwo(c) =>
1208 (Rsh64x64
1209 (Add64 <t> n (Rsh64Ux64 <t> (Rsh64x64 <t> n (Const64 <typ.UInt64> [63])) (Const64 <typ.UInt64> [int64(64-log64(c))])))
1210 (Const64 <typ.UInt64> [int64(log64(c))]))
1211
1212 // Signed divide, not a power of 2. Strength reduce to a multiply.
1213 (Div8 <t> x (Const8 [c])) && smagicOK8(c) =>
1214 (Sub8 <t>
1215 (Rsh32x64 <t>
1216 (Mul32 <typ.UInt32>
1217 (Const32 <typ.UInt32> [int32(smagic8(c).m)])
1218 (SignExt8to32 x))
1219 (Const64 <typ.UInt64> [8+smagic8(c).s]))
1220 (Rsh32x64 <t>
1221 (SignExt8to32 x)
1222 (Const64 <typ.UInt64> [31])))
1223 (Div16 <t> x (Const16 [c])) && smagicOK16(c) =>
1224 (Sub16 <t>
1225 (Rsh32x64 <t>
1226 (Mul32 <typ.UInt32>
1227 (Const32 <typ.UInt32> [int32(smagic16(c).m)])
1228 (SignExt16to32 x))
1229 (Const64 <typ.UInt64> [16+smagic16(c).s]))
1230 (Rsh32x64 <t>
1231 (SignExt16to32 x)
1232 (Const64 <typ.UInt64> [31])))
1233 (Div32 <t> x (Const32 [c])) && smagicOK32(c) && config.RegSize == 8 =>
1234 (Sub32 <t>
1235 (Rsh64x64 <t>
1236 (Mul64 <typ.UInt64>
1237 (Const64 <typ.UInt64> [int64(smagic32(c).m)])
1238 (SignExt32to64 x))
1239 (Const64 <typ.UInt64> [32+smagic32(c).s]))
1240 (Rsh64x64 <t>
1241 (SignExt32to64 x)
1242 (Const64 <typ.UInt64> [63])))
1243 (Div32 <t> x (Const32 [c])) && smagicOK32(c) && config.RegSize == 4 && smagic32(c).m&1 == 0 && config.useHmul =>
1244 (Sub32 <t>
1245 (Rsh32x64 <t>
1246 (Hmul32 <t>
1247 (Const32 <typ.UInt32> [int32(smagic32(c).m/2)])
1248 x)
1249 (Const64 <typ.UInt64> [smagic32(c).s-1]))
1250 (Rsh32x64 <t>
1251 x
1252 (Const64 <typ.UInt64> [31])))
1253 (Div32 <t> x (Const32 [c])) && smagicOK32(c) && config.RegSize == 4 && smagic32(c).m&1 != 0 && config.useHmul =>
1254 (Sub32 <t>
1255 (Rsh32x64 <t>
1256 (Add32 <t>
1257 (Hmul32 <t>
1258 (Const32 <typ.UInt32> [int32(smagic32(c).m)])
1259 x)
1260 x)
1261 (Const64 <typ.UInt64> [smagic32(c).s]))
1262 (Rsh32x64 <t>
1263 x
1264 (Const64 <typ.UInt64> [31])))
1265 (Div64 <t> x (Const64 [c])) && smagicOK64(c) && smagic64(c).m&1 == 0 && config.useHmul =>
1266 (Sub64 <t>
1267 (Rsh64x64 <t>
1268 (Hmul64 <t>
1269 (Const64 <typ.UInt64> [int64(smagic64(c).m/2)])
1270 x)
1271 (Const64 <typ.UInt64> [smagic64(c).s-1]))
1272 (Rsh64x64 <t>
1273 x
1274 (Const64 <typ.UInt64> [63])))
1275 (Div64 <t> x (Const64 [c])) && smagicOK64(c) && smagic64(c).m&1 != 0 && config.useHmul =>
1276 (Sub64 <t>
1277 (Rsh64x64 <t>
1278 (Add64 <t>
1279 (Hmul64 <t>
1280 (Const64 <typ.UInt64> [int64(smagic64(c).m)])
1281 x)
1282 x)
1283 (Const64 <typ.UInt64> [smagic64(c).s]))
1284 (Rsh64x64 <t>
1285 x
1286 (Const64 <typ.UInt64> [63])))
1287
1288 // Unsigned mod by power of 2 constant.
1289 (Mod8u <t> n (Const8 [c])) && isPowerOfTwo(c) => (And8 n (Const8 <t> [c-1]))
1290 (Mod16u <t> n (Const16 [c])) && isPowerOfTwo(c) => (And16 n (Const16 <t> [c-1]))
1291 (Mod32u <t> n (Const32 [c])) && isPowerOfTwo(c) => (And32 n (Const32 <t> [c-1]))
1292 (Mod64u <t> n (Const64 [c])) && isPowerOfTwo(c) => (And64 n (Const64 <t> [c-1]))
1293 (Mod64u <t> n (Const64 [-1<<63])) => (And64 n (Const64 <t> [1<<63-1]))
1294
1295 // Signed non-negative mod by power of 2 constant.
1296 (Mod8 <t> n (Const8 [c])) && isNonNegative(n) && isPowerOfTwo(c) => (And8 n (Const8 <t> [c-1]))
1297 (Mod16 <t> n (Const16 [c])) && isNonNegative(n) && isPowerOfTwo(c) => (And16 n (Const16 <t> [c-1]))
1298 (Mod32 <t> n (Const32 [c])) && isNonNegative(n) && isPowerOfTwo(c) => (And32 n (Const32 <t> [c-1]))
1299 (Mod64 <t> n (Const64 [c])) && isNonNegative(n) && isPowerOfTwo(c) => (And64 n (Const64 <t> [c-1]))
1300 (Mod64 n (Const64 [-1<<63])) && isNonNegative(n) => n
1301
1302 // Signed mod by negative constant.
1303 (Mod8 <t> n (Const8 [c])) && c < 0 && c != -1<<7 => (Mod8 <t> n (Const8 <t> [-c]))
1304 (Mod16 <t> n (Const16 [c])) && c < 0 && c != -1<<15 => (Mod16 <t> n (Const16 <t> [-c]))
1305 (Mod32 <t> n (Const32 [c])) && c < 0 && c != -1<<31 => (Mod32 <t> n (Const32 <t> [-c]))
1306 (Mod64 <t> n (Const64 [c])) && c < 0 && c != -1<<63 => (Mod64 <t> n (Const64 <t> [-c]))
1307
1308 // All other mods by constants, do A%B = A-(A/B*B).
1309 // This implements % with two * and a bunch of ancillary ops.
1310 // One of the * is free if the user's code also computes A/B.
1311 (Mod8 <t> x (Const8 [c])) && x.Op != OpConst8 && (c > 0 || c == -1<<7)
1312 => (Sub8 x (Mul8 <t> (Div8 <t> x (Const8 <t> [c])) (Const8 <t> [c])))
1313 (Mod16 <t> x (Const16 [c])) && x.Op != OpConst16 && (c > 0 || c == -1<<15)
1314 => (Sub16 x (Mul16 <t> (Div16 <t> x (Const16 <t> [c])) (Const16 <t> [c])))
1315 (Mod32 <t> x (Const32 [c])) && x.Op != OpConst32 && (c > 0 || c == -1<<31)
1316 => (Sub32 x (Mul32 <t> (Div32 <t> x (Const32 <t> [c])) (Const32 <t> [c])))
1317 (Mod64 <t> x (Const64 [c])) && x.Op != OpConst64 && (c > 0 || c == -1<<63)
1318 => (Sub64 x (Mul64 <t> (Div64 <t> x (Const64 <t> [c])) (Const64 <t> [c])))
1319 (Mod8u <t> x (Const8 [c])) && x.Op != OpConst8 && c > 0 && umagicOK8( c)
1320 => (Sub8 x (Mul8 <t> (Div8u <t> x (Const8 <t> [c])) (Const8 <t> [c])))
1321 (Mod16u <t> x (Const16 [c])) && x.Op != OpConst16 && c > 0 && umagicOK16(c)
1322 => (Sub16 x (Mul16 <t> (Div16u <t> x (Const16 <t> [c])) (Const16 <t> [c])))
1323 (Mod32u <t> x (Const32 [c])) && x.Op != OpConst32 && c > 0 && umagicOK32(c)
1324 => (Sub32 x (Mul32 <t> (Div32u <t> x (Const32 <t> [c])) (Const32 <t> [c])))
1325 (Mod64u <t> x (Const64 [c])) && x.Op != OpConst64 && c > 0 && umagicOK64(c)
1326 => (Sub64 x (Mul64 <t> (Div64u <t> x (Const64 <t> [c])) (Const64 <t> [c])))
1327
1328 // For architectures without rotates on less than 32-bits, promote these checks to 32-bit.
1329 (Eq8 (Mod8u x (Const8 [c])) (Const8 [0])) && x.Op != OpConst8 && udivisibleOK8(c) && !hasSmallRotate(config) =>
1330 (Eq32 (Mod32u <typ.UInt32> (ZeroExt8to32 <typ.UInt32> x) (Const32 <typ.UInt32> [int32(uint8(c))])) (Const32 <typ.UInt32> [0]))
1331 (Eq16 (Mod16u x (Const16 [c])) (Const16 [0])) && x.Op != OpConst16 && udivisibleOK16(c) && !hasSmallRotate(config) =>
1332 (Eq32 (Mod32u <typ.UInt32> (ZeroExt16to32 <typ.UInt32> x) (Const32 <typ.UInt32> [int32(uint16(c))])) (Const32 <typ.UInt32> [0]))
1333 (Eq8 (Mod8 x (Const8 [c])) (Const8 [0])) && x.Op != OpConst8 && sdivisibleOK8(c) && !hasSmallRotate(config) =>
1334 (Eq32 (Mod32 <typ.Int32> (SignExt8to32 <typ.Int32> x) (Const32 <typ.Int32> [int32(c)])) (Const32 <typ.Int32> [0]))
1335 (Eq16 (Mod16 x (Const16 [c])) (Const16 [0])) && x.Op != OpConst16 && sdivisibleOK16(c) && !hasSmallRotate(config) =>
1336 (Eq32 (Mod32 <typ.Int32> (SignExt16to32 <typ.Int32> x) (Const32 <typ.Int32> [int32(c)])) (Const32 <typ.Int32> [0]))
1337
1338 // Divisibility checks x%c == 0 convert to multiply and rotate.
1339 // Note, x%c == 0 is rewritten as x == c*(x/c) during the opt pass
1340 // where (x/c) is performed using multiplication with magic constants.
1341 // To rewrite x%c == 0 requires pattern matching the rewritten expression
1342 // and checking that the division by the same constant wasn't already calculated.
1343 // This check is made by counting uses of the magic constant multiplication.
1344 // Note that if there were an intermediate opt pass, this rule could be applied
1345 // directly on the Div op and magic division rewrites could be delayed to late opt.
1346
1347 // Unsigned divisibility checks convert to multiply and rotate.
1348 (Eq8 x (Mul8 (Const8 [c])
1349 (Trunc32to8
1350 (Rsh32Ux64
1351 mul:(Mul32
1352 (Const32 [m])
1353 (ZeroExt8to32 x))
1354 (Const64 [s])))
1355 )
1356 )
1357 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1358 && m == int32(1<<8+umagic8(c).m) && s == 8+umagic8(c).s
1359 && x.Op != OpConst8 && udivisibleOK8(c)
1360 => (Leq8U
1361 (RotateLeft8 <typ.UInt8>
1362 (Mul8 <typ.UInt8>
1363 (Const8 <typ.UInt8> [int8(udivisible8(c).m)])
1364 x)
1365 (Const8 <typ.UInt8> [int8(8-udivisible8(c).k)])
1366 )
1367 (Const8 <typ.UInt8> [int8(udivisible8(c).max)])
1368 )
1369
1370 (Eq16 x (Mul16 (Const16 [c])
1371 (Trunc64to16
1372 (Rsh64Ux64
1373 mul:(Mul64
1374 (Const64 [m])
1375 (ZeroExt16to64 x))
1376 (Const64 [s])))
1377 )
1378 )
1379 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1380 && m == int64(1<<16+umagic16(c).m) && s == 16+umagic16(c).s
1381 && x.Op != OpConst16 && udivisibleOK16(c)
1382 => (Leq16U
1383 (RotateLeft16 <typ.UInt16>
1384 (Mul16 <typ.UInt16>
1385 (Const16 <typ.UInt16> [int16(udivisible16(c).m)])
1386 x)
1387 (Const16 <typ.UInt16> [int16(16-udivisible16(c).k)])
1388 )
1389 (Const16 <typ.UInt16> [int16(udivisible16(c).max)])
1390 )
1391
1392 (Eq16 x (Mul16 (Const16 [c])
1393 (Trunc32to16
1394 (Rsh32Ux64
1395 mul:(Mul32
1396 (Const32 [m])
1397 (ZeroExt16to32 x))
1398 (Const64 [s])))
1399 )
1400 )
1401 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1402 && m == int32(1<<15+umagic16(c).m/2) && s == 16+umagic16(c).s-1
1403 && x.Op != OpConst16 && udivisibleOK16(c)
1404 => (Leq16U
1405 (RotateLeft16 <typ.UInt16>
1406 (Mul16 <typ.UInt16>
1407 (Const16 <typ.UInt16> [int16(udivisible16(c).m)])
1408 x)
1409 (Const16 <typ.UInt16> [int16(16-udivisible16(c).k)])
1410 )
1411 (Const16 <typ.UInt16> [int16(udivisible16(c).max)])
1412 )
1413
1414 (Eq16 x (Mul16 (Const16 [c])
1415 (Trunc32to16
1416 (Rsh32Ux64
1417 mul:(Mul32
1418 (Const32 [m])
1419 (Rsh32Ux64 (ZeroExt16to32 x) (Const64 [1])))
1420 (Const64 [s])))
1421 )
1422 )
1423 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1424 && m == int32(1<<15+(umagic16(c).m+1)/2) && s == 16+umagic16(c).s-2
1425 && x.Op != OpConst16 && udivisibleOK16(c)
1426 => (Leq16U
1427 (RotateLeft16 <typ.UInt16>
1428 (Mul16 <typ.UInt16>
1429 (Const16 <typ.UInt16> [int16(udivisible16(c).m)])
1430 x)
1431 (Const16 <typ.UInt16> [int16(16-udivisible16(c).k)])
1432 )
1433 (Const16 <typ.UInt16> [int16(udivisible16(c).max)])
1434 )
1435
1436 (Eq16 x (Mul16 (Const16 [c])
1437 (Trunc32to16
1438 (Rsh32Ux64
1439 (Avg32u
1440 (Lsh32x64 (ZeroExt16to32 x) (Const64 [16]))
1441 mul:(Mul32
1442 (Const32 [m])
1443 (ZeroExt16to32 x)))
1444 (Const64 [s])))
1445 )
1446 )
1447 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1448 && m == int32(umagic16(c).m) && s == 16+umagic16(c).s-1
1449 && x.Op != OpConst16 && udivisibleOK16(c)
1450 => (Leq16U
1451 (RotateLeft16 <typ.UInt16>
1452 (Mul16 <typ.UInt16>
1453 (Const16 <typ.UInt16> [int16(udivisible16(c).m)])
1454 x)
1455 (Const16 <typ.UInt16> [int16(16-udivisible16(c).k)])
1456 )
1457 (Const16 <typ.UInt16> [int16(udivisible16(c).max)])
1458 )
1459
1460 (Eq32 x (Mul32 (Const32 [c])
1461 (Rsh32Ux64
1462 mul:(Hmul32u
1463 (Const32 [m])
1464 x)
1465 (Const64 [s]))
1466 )
1467 )
1468 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1469 && m == int32(1<<31+umagic32(c).m/2) && s == umagic32(c).s-1
1470 && x.Op != OpConst32 && udivisibleOK32(c)
1471 => (Leq32U
1472 (RotateLeft32 <typ.UInt32>
1473 (Mul32 <typ.UInt32>
1474 (Const32 <typ.UInt32> [int32(udivisible32(c).m)])
1475 x)
1476 (Const32 <typ.UInt32> [int32(32-udivisible32(c).k)])
1477 )
1478 (Const32 <typ.UInt32> [int32(udivisible32(c).max)])
1479 )
1480
1481 (Eq32 x (Mul32 (Const32 [c])
1482 (Rsh32Ux64
1483 mul:(Hmul32u
1484 (Const32 <typ.UInt32> [m])
1485 (Rsh32Ux64 x (Const64 [1])))
1486 (Const64 [s]))
1487 )
1488 )
1489 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1490 && m == int32(1<<31+(umagic32(c).m+1)/2) && s == umagic32(c).s-2
1491 && x.Op != OpConst32 && udivisibleOK32(c)
1492 => (Leq32U
1493 (RotateLeft32 <typ.UInt32>
1494 (Mul32 <typ.UInt32>
1495 (Const32 <typ.UInt32> [int32(udivisible32(c).m)])
1496 x)
1497 (Const32 <typ.UInt32> [int32(32-udivisible32(c).k)])
1498 )
1499 (Const32 <typ.UInt32> [int32(udivisible32(c).max)])
1500 )
1501
1502 (Eq32 x (Mul32 (Const32 [c])
1503 (Rsh32Ux64
1504 (Avg32u
1505 x
1506 mul:(Hmul32u
1507 (Const32 [m])
1508 x))
1509 (Const64 [s]))
1510 )
1511 )
1512 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1513 && m == int32(umagic32(c).m) && s == umagic32(c).s-1
1514 && x.Op != OpConst32 && udivisibleOK32(c)
1515 => (Leq32U
1516 (RotateLeft32 <typ.UInt32>
1517 (Mul32 <typ.UInt32>
1518 (Const32 <typ.UInt32> [int32(udivisible32(c).m)])
1519 x)
1520 (Const32 <typ.UInt32> [int32(32-udivisible32(c).k)])
1521 )
1522 (Const32 <typ.UInt32> [int32(udivisible32(c).max)])
1523 )
1524
1525 (Eq32 x (Mul32 (Const32 [c])
1526 (Trunc64to32
1527 (Rsh64Ux64
1528 mul:(Mul64
1529 (Const64 [m])
1530 (ZeroExt32to64 x))
1531 (Const64 [s])))
1532 )
1533 )
1534 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1535 && m == int64(1<<31+umagic32(c).m/2) && s == 32+umagic32(c).s-1
1536 && x.Op != OpConst32 && udivisibleOK32(c)
1537 => (Leq32U
1538 (RotateLeft32 <typ.UInt32>
1539 (Mul32 <typ.UInt32>
1540 (Const32 <typ.UInt32> [int32(udivisible32(c).m)])
1541 x)
1542 (Const32 <typ.UInt32> [int32(32-udivisible32(c).k)])
1543 )
1544 (Const32 <typ.UInt32> [int32(udivisible32(c).max)])
1545 )
1546
1547 (Eq32 x (Mul32 (Const32 [c])
1548 (Trunc64to32
1549 (Rsh64Ux64
1550 mul:(Mul64
1551 (Const64 [m])
1552 (Rsh64Ux64 (ZeroExt32to64 x) (Const64 [1])))
1553 (Const64 [s])))
1554 )
1555 )
1556 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1557 && m == int64(1<<31+(umagic32(c).m+1)/2) && s == 32+umagic32(c).s-2
1558 && x.Op != OpConst32 && udivisibleOK32(c)
1559 => (Leq32U
1560 (RotateLeft32 <typ.UInt32>
1561 (Mul32 <typ.UInt32>
1562 (Const32 <typ.UInt32> [int32(udivisible32(c).m)])
1563 x)
1564 (Const32 <typ.UInt32> [int32(32-udivisible32(c).k)])
1565 )
1566 (Const32 <typ.UInt32> [int32(udivisible32(c).max)])
1567 )
1568
1569 (Eq32 x (Mul32 (Const32 [c])
1570 (Trunc64to32
1571 (Rsh64Ux64
1572 (Avg64u
1573 (Lsh64x64 (ZeroExt32to64 x) (Const64 [32]))
1574 mul:(Mul64
1575 (Const64 [m])
1576 (ZeroExt32to64 x)))
1577 (Const64 [s])))
1578 )
1579 )
1580 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1581 && m == int64(umagic32(c).m) && s == 32+umagic32(c).s-1
1582 && x.Op != OpConst32 && udivisibleOK32(c)
1583 => (Leq32U
1584 (RotateLeft32 <typ.UInt32>
1585 (Mul32 <typ.UInt32>
1586 (Const32 <typ.UInt32> [int32(udivisible32(c).m)])
1587 x)
1588 (Const32 <typ.UInt32> [int32(32-udivisible32(c).k)])
1589 )
1590 (Const32 <typ.UInt32> [int32(udivisible32(c).max)])
1591 )
1592
1593 (Eq64 x (Mul64 (Const64 [c])
1594 (Rsh64Ux64
1595 mul:(Hmul64u
1596 (Const64 [m])
1597 x)
1598 (Const64 [s]))
1599 )
1600 ) && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1601 && m == int64(1<<63+umagic64(c).m/2) && s == umagic64(c).s-1
1602 && x.Op != OpConst64 && udivisibleOK64(c)
1603 => (Leq64U
1604 (RotateLeft64 <typ.UInt64>
1605 (Mul64 <typ.UInt64>
1606 (Const64 <typ.UInt64> [int64(udivisible64(c).m)])
1607 x)
1608 (Const64 <typ.UInt64> [64-udivisible64(c).k])
1609 )
1610 (Const64 <typ.UInt64> [int64(udivisible64(c).max)])
1611 )
1612 (Eq64 x (Mul64 (Const64 [c])
1613 (Rsh64Ux64
1614 mul:(Hmul64u
1615 (Const64 [m])
1616 (Rsh64Ux64 x (Const64 [1])))
1617 (Const64 [s]))
1618 )
1619 ) && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1620 && m == int64(1<<63+(umagic64(c).m+1)/2) && s == umagic64(c).s-2
1621 && x.Op != OpConst64 && udivisibleOK64(c)
1622 => (Leq64U
1623 (RotateLeft64 <typ.UInt64>
1624 (Mul64 <typ.UInt64>
1625 (Const64 <typ.UInt64> [int64(udivisible64(c).m)])
1626 x)
1627 (Const64 <typ.UInt64> [64-udivisible64(c).k])
1628 )
1629 (Const64 <typ.UInt64> [int64(udivisible64(c).max)])
1630 )
1631 (Eq64 x (Mul64 (Const64 [c])
1632 (Rsh64Ux64
1633 (Avg64u
1634 x
1635 mul:(Hmul64u
1636 (Const64 [m])
1637 x))
1638 (Const64 [s]))
1639 )
1640 ) && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1641 && m == int64(umagic64(c).m) && s == umagic64(c).s-1
1642 && x.Op != OpConst64 && udivisibleOK64(c)
1643 => (Leq64U
1644 (RotateLeft64 <typ.UInt64>
1645 (Mul64 <typ.UInt64>
1646 (Const64 <typ.UInt64> [int64(udivisible64(c).m)])
1647 x)
1648 (Const64 <typ.UInt64> [64-udivisible64(c).k])
1649 )
1650 (Const64 <typ.UInt64> [int64(udivisible64(c).max)])
1651 )
1652
1653 // Signed divisibility checks convert to multiply, add and rotate.
1654 (Eq8 x (Mul8 (Const8 [c])
1655 (Sub8
1656 (Rsh32x64
1657 mul:(Mul32
1658 (Const32 [m])
1659 (SignExt8to32 x))
1660 (Const64 [s]))
1661 (Rsh32x64
1662 (SignExt8to32 x)
1663 (Const64 [31])))
1664 )
1665 )
1666 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1667 && m == int32(smagic8(c).m) && s == 8+smagic8(c).s
1668 && x.Op != OpConst8 && sdivisibleOK8(c)
1669 => (Leq8U
1670 (RotateLeft8 <typ.UInt8>
1671 (Add8 <typ.UInt8>
1672 (Mul8 <typ.UInt8>
1673 (Const8 <typ.UInt8> [int8(sdivisible8(c).m)])
1674 x)
1675 (Const8 <typ.UInt8> [int8(sdivisible8(c).a)])
1676 )
1677 (Const8 <typ.UInt8> [int8(8-sdivisible8(c).k)])
1678 )
1679 (Const8 <typ.UInt8> [int8(sdivisible8(c).max)])
1680 )
1681
1682 (Eq16 x (Mul16 (Const16 [c])
1683 (Sub16
1684 (Rsh32x64
1685 mul:(Mul32
1686 (Const32 [m])
1687 (SignExt16to32 x))
1688 (Const64 [s]))
1689 (Rsh32x64
1690 (SignExt16to32 x)
1691 (Const64 [31])))
1692 )
1693 )
1694 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1695 && m == int32(smagic16(c).m) && s == 16+smagic16(c).s
1696 && x.Op != OpConst16 && sdivisibleOK16(c)
1697 => (Leq16U
1698 (RotateLeft16 <typ.UInt16>
1699 (Add16 <typ.UInt16>
1700 (Mul16 <typ.UInt16>
1701 (Const16 <typ.UInt16> [int16(sdivisible16(c).m)])
1702 x)
1703 (Const16 <typ.UInt16> [int16(sdivisible16(c).a)])
1704 )
1705 (Const16 <typ.UInt16> [int16(16-sdivisible16(c).k)])
1706 )
1707 (Const16 <typ.UInt16> [int16(sdivisible16(c).max)])
1708 )
1709
1710 (Eq32 x (Mul32 (Const32 [c])
1711 (Sub32
1712 (Rsh64x64
1713 mul:(Mul64
1714 (Const64 [m])
1715 (SignExt32to64 x))
1716 (Const64 [s]))
1717 (Rsh64x64
1718 (SignExt32to64 x)
1719 (Const64 [63])))
1720 )
1721 )
1722 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1723 && m == int64(smagic32(c).m) && s == 32+smagic32(c).s
1724 && x.Op != OpConst32 && sdivisibleOK32(c)
1725 => (Leq32U
1726 (RotateLeft32 <typ.UInt32>
1727 (Add32 <typ.UInt32>
1728 (Mul32 <typ.UInt32>
1729 (Const32 <typ.UInt32> [int32(sdivisible32(c).m)])
1730 x)
1731 (Const32 <typ.UInt32> [int32(sdivisible32(c).a)])
1732 )
1733 (Const32 <typ.UInt32> [int32(32-sdivisible32(c).k)])
1734 )
1735 (Const32 <typ.UInt32> [int32(sdivisible32(c).max)])
1736 )
1737
1738 (Eq32 x (Mul32 (Const32 [c])
1739 (Sub32
1740 (Rsh32x64
1741 mul:(Hmul32
1742 (Const32 [m])
1743 x)
1744 (Const64 [s]))
1745 (Rsh32x64
1746 x
1747 (Const64 [31])))
1748 )
1749 )
1750 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1751 && m == int32(smagic32(c).m/2) && s == smagic32(c).s-1
1752 && x.Op != OpConst32 && sdivisibleOK32(c)
1753 => (Leq32U
1754 (RotateLeft32 <typ.UInt32>
1755 (Add32 <typ.UInt32>
1756 (Mul32 <typ.UInt32>
1757 (Const32 <typ.UInt32> [int32(sdivisible32(c).m)])
1758 x)
1759 (Const32 <typ.UInt32> [int32(sdivisible32(c).a)])
1760 )
1761 (Const32 <typ.UInt32> [int32(32-sdivisible32(c).k)])
1762 )
1763 (Const32 <typ.UInt32> [int32(sdivisible32(c).max)])
1764 )
1765
1766 (Eq32 x (Mul32 (Const32 [c])
1767 (Sub32
1768 (Rsh32x64
1769 (Add32
1770 mul:(Hmul32
1771 (Const32 [m])
1772 x)
1773 x)
1774 (Const64 [s]))
1775 (Rsh32x64
1776 x
1777 (Const64 [31])))
1778 )
1779 )
1780 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1781 && m == int32(smagic32(c).m) && s == smagic32(c).s
1782 && x.Op != OpConst32 && sdivisibleOK32(c)
1783 => (Leq32U
1784 (RotateLeft32 <typ.UInt32>
1785 (Add32 <typ.UInt32>
1786 (Mul32 <typ.UInt32>
1787 (Const32 <typ.UInt32> [int32(sdivisible32(c).m)])
1788 x)
1789 (Const32 <typ.UInt32> [int32(sdivisible32(c).a)])
1790 )
1791 (Const32 <typ.UInt32> [int32(32-sdivisible32(c).k)])
1792 )
1793 (Const32 <typ.UInt32> [int32(sdivisible32(c).max)])
1794 )
1795
1796 (Eq64 x (Mul64 (Const64 [c])
1797 (Sub64
1798 (Rsh64x64
1799 mul:(Hmul64
1800 (Const64 [m])
1801 x)
1802 (Const64 [s]))
1803 (Rsh64x64
1804 x
1805 (Const64 [63])))
1806 )
1807 )
1808 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1809 && m == int64(smagic64(c).m/2) && s == smagic64(c).s-1
1810 && x.Op != OpConst64 && sdivisibleOK64(c)
1811 => (Leq64U
1812 (RotateLeft64 <typ.UInt64>
1813 (Add64 <typ.UInt64>
1814 (Mul64 <typ.UInt64>
1815 (Const64 <typ.UInt64> [int64(sdivisible64(c).m)])
1816 x)
1817 (Const64 <typ.UInt64> [int64(sdivisible64(c).a)])
1818 )
1819 (Const64 <typ.UInt64> [64-sdivisible64(c).k])
1820 )
1821 (Const64 <typ.UInt64> [int64(sdivisible64(c).max)])
1822 )
1823
1824 (Eq64 x (Mul64 (Const64 [c])
1825 (Sub64
1826 (Rsh64x64
1827 (Add64
1828 mul:(Hmul64
1829 (Const64 [m])
1830 x)
1831 x)
1832 (Const64 [s]))
1833 (Rsh64x64
1834 x
1835 (Const64 [63])))
1836 )
1837 )
1838 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1839 && m == int64(smagic64(c).m) && s == smagic64(c).s
1840 && x.Op != OpConst64 && sdivisibleOK64(c)
1841 => (Leq64U
1842 (RotateLeft64 <typ.UInt64>
1843 (Add64 <typ.UInt64>
1844 (Mul64 <typ.UInt64>
1845 (Const64 <typ.UInt64> [int64(sdivisible64(c).m)])
1846 x)
1847 (Const64 <typ.UInt64> [int64(sdivisible64(c).a)])
1848 )
1849 (Const64 <typ.UInt64> [64-sdivisible64(c).k])
1850 )
1851 (Const64 <typ.UInt64> [int64(sdivisible64(c).max)])
1852 )
1853
1854 // Divisibility check for signed integers for power of two constant are simple mask.
1855 // However, we must match against the rewritten n%c == 0 -> n - c*(n/c) == 0 -> n == c*(n/c)
1856 // where n/c contains fixup code to handle signed n.
1857 ((Eq8|Neq8) n (Lsh8x64
1858 (Rsh8x64
1859 (Add8 <t> n (Rsh8Ux64 <t> (Rsh8x64 <t> n (Const64 <typ.UInt64> [ 7])) (Const64 <typ.UInt64> [kbar])))
1860 (Const64 <typ.UInt64> [k]))
1861 (Const64 <typ.UInt64> [k]))
1862 ) && k > 0 && k < 7 && kbar == 8 - k
1863 => ((Eq8|Neq8) (And8 <t> n (Const8 <t> [1<<uint(k)-1])) (Const8 <t> [0]))
1864
1865 ((Eq16|Neq16) n (Lsh16x64
1866 (Rsh16x64
1867 (Add16 <t> n (Rsh16Ux64 <t> (Rsh16x64 <t> n (Const64 <typ.UInt64> [15])) (Const64 <typ.UInt64> [kbar])))
1868 (Const64 <typ.UInt64> [k]))
1869 (Const64 <typ.UInt64> [k]))
1870 ) && k > 0 && k < 15 && kbar == 16 - k
1871 => ((Eq16|Neq16) (And16 <t> n (Const16 <t> [1<<uint(k)-1])) (Const16 <t> [0]))
1872
1873 ((Eq32|Neq32) n (Lsh32x64
1874 (Rsh32x64
1875 (Add32 <t> n (Rsh32Ux64 <t> (Rsh32x64 <t> n (Const64 <typ.UInt64> [31])) (Const64 <typ.UInt64> [kbar])))
1876 (Const64 <typ.UInt64> [k]))
1877 (Const64 <typ.UInt64> [k]))
1878 ) && k > 0 && k < 31 && kbar == 32 - k
1879 => ((Eq32|Neq32) (And32 <t> n (Const32 <t> [1<<uint(k)-1])) (Const32 <t> [0]))
1880
1881 ((Eq64|Neq64) n (Lsh64x64
1882 (Rsh64x64
1883 (Add64 <t> n (Rsh64Ux64 <t> (Rsh64x64 <t> n (Const64 <typ.UInt64> [63])) (Const64 <typ.UInt64> [kbar])))
1884 (Const64 <typ.UInt64> [k]))
1885 (Const64 <typ.UInt64> [k]))
1886 ) && k > 0 && k < 63 && kbar == 64 - k
1887 => ((Eq64|Neq64) (And64 <t> n (Const64 <t> [1<<uint(k)-1])) (Const64 <t> [0]))
1888
1889 (Eq(8|16|32|64) s:(Sub(8|16|32|64) x y) (Const(8|16|32|64) [0])) && s.Uses == 1 => (Eq(8|16|32|64) x y)
1890 (Neq(8|16|32|64) s:(Sub(8|16|32|64) x y) (Const(8|16|32|64) [0])) && s.Uses == 1 => (Neq(8|16|32|64) x y)
1891
1892 // Optimize bitsets
1893 (Eq8 (And8 <t> x (Const8 <t> [y])) (Const8 <t> [y])) && oneBit8(y)
1894 => (Neq8 (And8 <t> x (Const8 <t> [y])) (Const8 <t> [0]))
1895 (Eq16 (And16 <t> x (Const16 <t> [y])) (Const16 <t> [y])) && oneBit16(y)
1896 => (Neq16 (And16 <t> x (Const16 <t> [y])) (Const16 <t> [0]))
1897 (Eq32 (And32 <t> x (Const32 <t> [y])) (Const32 <t> [y])) && oneBit32(y)
1898 => (Neq32 (And32 <t> x (Const32 <t> [y])) (Const32 <t> [0]))
1899 (Eq64 (And64 <t> x (Const64 <t> [y])) (Const64 <t> [y])) && oneBit64(y)
1900 => (Neq64 (And64 <t> x (Const64 <t> [y])) (Const64 <t> [0]))
1901 (Neq8 (And8 <t> x (Const8 <t> [y])) (Const8 <t> [y])) && oneBit8(y)
1902 => (Eq8 (And8 <t> x (Const8 <t> [y])) (Const8 <t> [0]))
1903 (Neq16 (And16 <t> x (Const16 <t> [y])) (Const16 <t> [y])) && oneBit16(y)
1904 => (Eq16 (And16 <t> x (Const16 <t> [y])) (Const16 <t> [0]))
1905 (Neq32 (And32 <t> x (Const32 <t> [y])) (Const32 <t> [y])) && oneBit32(y)
1906 => (Eq32 (And32 <t> x (Const32 <t> [y])) (Const32 <t> [0]))
1907 (Neq64 (And64 <t> x (Const64 <t> [y])) (Const64 <t> [y])) && oneBit64(y)
1908 => (Eq64 (And64 <t> x (Const64 <t> [y])) (Const64 <t> [0]))
1909
1910 // Reassociate expressions involving
1911 // constants such that constants come first,
1912 // exposing obvious constant-folding opportunities.
1913 // Reassociate (op (op y C) x) to (op C (op x y)) or similar, where C
1914 // is constant, which pushes constants to the outside
1915 // of the expression. At that point, any constant-folding
1916 // opportunities should be obvious.
1917 // Note: don't include AddPtr here! In order to maintain the
1918 // invariant that pointers must stay within the pointed-to object,
1919 // we can't pull part of a pointer computation above the AddPtr.
1920 // See issue 37881.
1921 // Note: we don't need to handle any (x-C) cases because we already rewrite
1922 // (x-C) to (x+(-C)).
1923
1924 // x + (C + z) -> C + (x + z)
1925 (Add64 (Add64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Add64 i (Add64 <t> z x))
1926 (Add32 (Add32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Add32 i (Add32 <t> z x))
1927 (Add16 (Add16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Add16 i (Add16 <t> z x))
1928 (Add8 (Add8 i:(Const8 <t>) z) x) && (z.Op != OpConst8 && x.Op != OpConst8) => (Add8 i (Add8 <t> z x))
1929
1930 // x + (C - z) -> C + (x - z)
1931 (Add64 (Sub64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Add64 i (Sub64 <t> x z))
1932 (Add32 (Sub32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Add32 i (Sub32 <t> x z))
1933 (Add16 (Sub16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Add16 i (Sub16 <t> x z))
1934 (Add8 (Sub8 i:(Const8 <t>) z) x) && (z.Op != OpConst8 && x.Op != OpConst8) => (Add8 i (Sub8 <t> x z))
1935
1936 // x - (C - z) -> x + (z - C) -> (x + z) - C
1937 (Sub64 x (Sub64 i:(Const64 <t>) z)) && (z.Op != OpConst64 && x.Op != OpConst64) => (Sub64 (Add64 <t> x z) i)
1938 (Sub32 x (Sub32 i:(Const32 <t>) z)) && (z.Op != OpConst32 && x.Op != OpConst32) => (Sub32 (Add32 <t> x z) i)
1939 (Sub16 x (Sub16 i:(Const16 <t>) z)) && (z.Op != OpConst16 && x.Op != OpConst16) => (Sub16 (Add16 <t> x z) i)
1940 (Sub8 x (Sub8 i:(Const8 <t>) z)) && (z.Op != OpConst8 && x.Op != OpConst8) => (Sub8 (Add8 <t> x z) i)
1941
1942 // x - (z + C) -> x + (-z - C) -> (x - z) - C
1943 (Sub64 x (Add64 z i:(Const64 <t>))) && (z.Op != OpConst64 && x.Op != OpConst64) => (Sub64 (Sub64 <t> x z) i)
1944 (Sub32 x (Add32 z i:(Const32 <t>))) && (z.Op != OpConst32 && x.Op != OpConst32) => (Sub32 (Sub32 <t> x z) i)
1945 (Sub16 x (Add16 z i:(Const16 <t>))) && (z.Op != OpConst16 && x.Op != OpConst16) => (Sub16 (Sub16 <t> x z) i)
1946 (Sub8 x (Add8 z i:(Const8 <t>))) && (z.Op != OpConst8 && x.Op != OpConst8) => (Sub8 (Sub8 <t> x z) i)
1947
1948 // (C - z) - x -> C - (z + x)
1949 (Sub64 (Sub64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Sub64 i (Add64 <t> z x))
1950 (Sub32 (Sub32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Sub32 i (Add32 <t> z x))
1951 (Sub16 (Sub16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Sub16 i (Add16 <t> z x))
1952 (Sub8 (Sub8 i:(Const8 <t>) z) x) && (z.Op != OpConst8 && x.Op != OpConst8) => (Sub8 i (Add8 <t> z x))
1953
1954 // (z + C) -x -> C + (z - x)
1955 (Sub64 (Add64 z i:(Const64 <t>)) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Add64 i (Sub64 <t> z x))
1956 (Sub32 (Add32 z i:(Const32 <t>)) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Add32 i (Sub32 <t> z x))
1957 (Sub16 (Add16 z i:(Const16 <t>)) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Add16 i (Sub16 <t> z x))
1958 (Sub8 (Add8 z i:(Const8 <t>)) x) && (z.Op != OpConst8 && x.Op != OpConst8) => (Add8 i (Sub8 <t> z x))
1959
1960 // x & (C & z) -> C & (x & z)
1961 (And64 (And64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (And64 i (And64 <t> z x))
1962 (And32 (And32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (And32 i (And32 <t> z x))
1963 (And16 (And16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (And16 i (And16 <t> z x))
1964 (And8 (And8 i:(Const8 <t>) z) x) && (z.Op != OpConst8 && x.Op != OpConst8) => (And8 i (And8 <t> z x))
1965
1966 // x | (C | z) -> C | (x | z)
1967 (Or64 (Or64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Or64 i (Or64 <t> z x))
1968 (Or32 (Or32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Or32 i (Or32 <t> z x))
1969 (Or16 (Or16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Or16 i (Or16 <t> z x))
1970 (Or8 (Or8 i:(Const8 <t>) z) x) && (z.Op != OpConst8 && x.Op != OpConst8) => (Or8 i (Or8 <t> z x))
1971
1972 // x ^ (C ^ z) -> C ^ (x ^ z)
1973 (Xor64 (Xor64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Xor64 i (Xor64 <t> z x))
1974 (Xor32 (Xor32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Xor32 i (Xor32 <t> z x))
1975 (Xor16 (Xor16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Xor16 i (Xor16 <t> z x))
1976 (Xor8 (Xor8 i:(Const8 <t>) z) x) && (z.Op != OpConst8 && x.Op != OpConst8) => (Xor8 i (Xor8 <t> z x))
1977
1978 // x * (D * z) = D * (x * z)
1979 (Mul64 (Mul64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Mul64 i (Mul64 <t> x z))
1980 (Mul32 (Mul32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Mul32 i (Mul32 <t> x z))
1981 (Mul16 (Mul16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Mul16 i (Mul16 <t> x z))
1982 (Mul8 (Mul8 i:(Const8 <t>) z) x) && (z.Op != OpConst8 && x.Op != OpConst8) => (Mul8 i (Mul8 <t> x z))
1983
1984 // C + (D + x) -> (C + D) + x
1985 (Add64 (Const64 <t> [c]) (Add64 (Const64 <t> [d]) x)) => (Add64 (Const64 <t> [c+d]) x)
1986 (Add32 (Const32 <t> [c]) (Add32 (Const32 <t> [d]) x)) => (Add32 (Const32 <t> [c+d]) x)
1987 (Add16 (Const16 <t> [c]) (Add16 (Const16 <t> [d]) x)) => (Add16 (Const16 <t> [c+d]) x)
1988 (Add8 (Const8 <t> [c]) (Add8 (Const8 <t> [d]) x)) => (Add8 (Const8 <t> [c+d]) x)
1989
1990 // C + (D - x) -> (C + D) - x
1991 (Add64 (Const64 <t> [c]) (Sub64 (Const64 <t> [d]) x)) => (Sub64 (Const64 <t> [c+d]) x)
1992 (Add32 (Const32 <t> [c]) (Sub32 (Const32 <t> [d]) x)) => (Sub32 (Const32 <t> [c+d]) x)
1993 (Add16 (Const16 <t> [c]) (Sub16 (Const16 <t> [d]) x)) => (Sub16 (Const16 <t> [c+d]) x)
1994 (Add8 (Const8 <t> [c]) (Sub8 (Const8 <t> [d]) x)) => (Sub8 (Const8 <t> [c+d]) x)
1995
1996 // C - (D - x) -> (C - D) + x
1997 (Sub64 (Const64 <t> [c]) (Sub64 (Const64 <t> [d]) x)) => (Add64 (Const64 <t> [c-d]) x)
1998 (Sub32 (Const32 <t> [c]) (Sub32 (Const32 <t> [d]) x)) => (Add32 (Const32 <t> [c-d]) x)
1999 (Sub16 (Const16 <t> [c]) (Sub16 (Const16 <t> [d]) x)) => (Add16 (Const16 <t> [c-d]) x)
2000 (Sub8 (Const8 <t> [c]) (Sub8 (Const8 <t> [d]) x)) => (Add8 (Const8 <t> [c-d]) x)
2001
2002 // C - (D + x) -> (C - D) - x
2003 (Sub64 (Const64 <t> [c]) (Add64 (Const64 <t> [d]) x)) => (Sub64 (Const64 <t> [c-d]) x)
2004 (Sub32 (Const32 <t> [c]) (Add32 (Const32 <t> [d]) x)) => (Sub32 (Const32 <t> [c-d]) x)
2005 (Sub16 (Const16 <t> [c]) (Add16 (Const16 <t> [d]) x)) => (Sub16 (Const16 <t> [c-d]) x)
2006 (Sub8 (Const8 <t> [c]) (Add8 (Const8 <t> [d]) x)) => (Sub8 (Const8 <t> [c-d]) x)
2007
2008 // C & (D & x) -> (C & D) & x
2009 (And64 (Const64 <t> [c]) (And64 (Const64 <t> [d]) x)) => (And64 (Const64 <t> [c&d]) x)
2010 (And32 (Const32 <t> [c]) (And32 (Const32 <t> [d]) x)) => (And32 (Const32 <t> [c&d]) x)
2011 (And16 (Const16 <t> [c]) (And16 (Const16 <t> [d]) x)) => (And16 (Const16 <t> [c&d]) x)
2012 (And8 (Const8 <t> [c]) (And8 (Const8 <t> [d]) x)) => (And8 (Const8 <t> [c&d]) x)
2013
2014 // C | (D | x) -> (C | D) | x
2015 (Or64 (Const64 <t> [c]) (Or64 (Const64 <t> [d]) x)) => (Or64 (Const64 <t> [c|d]) x)
2016 (Or32 (Const32 <t> [c]) (Or32 (Const32 <t> [d]) x)) => (Or32 (Const32 <t> [c|d]) x)
2017 (Or16 (Const16 <t> [c]) (Or16 (Const16 <t> [d]) x)) => (Or16 (Const16 <t> [c|d]) x)
2018 (Or8 (Const8 <t> [c]) (Or8 (Const8 <t> [d]) x)) => (Or8 (Const8 <t> [c|d]) x)
2019
2020 // C ^ (D ^ x) -> (C ^ D) ^ x
2021 (Xor64 (Const64 <t> [c]) (Xor64 (Const64 <t> [d]) x)) => (Xor64 (Const64 <t> [c^d]) x)
2022 (Xor32 (Const32 <t> [c]) (Xor32 (Const32 <t> [d]) x)) => (Xor32 (Const32 <t> [c^d]) x)
2023 (Xor16 (Const16 <t> [c]) (Xor16 (Const16 <t> [d]) x)) => (Xor16 (Const16 <t> [c^d]) x)
2024 (Xor8 (Const8 <t> [c]) (Xor8 (Const8 <t> [d]) x)) => (Xor8 (Const8 <t> [c^d]) x)
2025
2026 // C * (D * x) = (C * D) * x
2027 (Mul64 (Const64 <t> [c]) (Mul64 (Const64 <t> [d]) x)) => (Mul64 (Const64 <t> [c*d]) x)
2028 (Mul32 (Const32 <t> [c]) (Mul32 (Const32 <t> [d]) x)) => (Mul32 (Const32 <t> [c*d]) x)
2029 (Mul16 (Const16 <t> [c]) (Mul16 (Const16 <t> [d]) x)) => (Mul16 (Const16 <t> [c*d]) x)
2030 (Mul8 (Const8 <t> [c]) (Mul8 (Const8 <t> [d]) x)) => (Mul8 (Const8 <t> [c*d]) x)
2031
2032 // floating point optimizations
2033 (Mul(32|64)F x (Const(32|64)F [1])) => x
2034 (Mul32F x (Const32F [-1])) => (Neg32F x)
2035 (Mul64F x (Const64F [-1])) => (Neg64F x)
2036 (Mul32F x (Const32F [2])) => (Add32F x x)
2037 (Mul64F x (Const64F [2])) => (Add64F x x)
2038
2039 (Div32F x (Const32F <t> [c])) && reciprocalExact32(c) => (Mul32F x (Const32F <t> [1/c]))
2040 (Div64F x (Const64F <t> [c])) && reciprocalExact64(c) => (Mul64F x (Const64F <t> [1/c]))
2041
2042 // rewrite single-precision sqrt expression "float32(math.Sqrt(float64(x)))"
2043 (Cvt64Fto32F sqrt0:(Sqrt (Cvt32Fto64F x))) && sqrt0.Uses==1 => (Sqrt32 x)
2044
2045 (Sqrt (Const64F [c])) && !math.IsNaN(math.Sqrt(c)) => (Const64F [math.Sqrt(c)])
2046
2047 // for rewriting constant folded math/bits ops
2048 (Select0 (MakeTuple x y)) => x
2049 (Select1 (MakeTuple x y)) => y
2050
2051 // for rewriting results of some late-expanded rewrites (below)
2052 (SelectN [0] (MakeResult x ___)) => x
2053 (SelectN [1] (MakeResult x y ___)) => y
2054 (SelectN [2] (MakeResult x y z ___)) => z
2055
2056 // for late-expanded calls, recognize newobject and remove zeroing and nilchecks
2057 (Zero (SelectN [0] call:(StaticLECall _ _)) mem:(SelectN [1] call))
2058 && isSameCall(call.Aux, "runtime.newobject")
2059 => mem
2060
2061 (Store (SelectN [0] call:(StaticLECall _ _)) x mem:(SelectN [1] call))
2062 && isConstZero(x)
2063 && isSameCall(call.Aux, "runtime.newobject")
2064 => mem
2065
2066 (Store (OffPtr (SelectN [0] call:(StaticLECall _ _))) x mem:(SelectN [1] call))
2067 && isConstZero(x)
2068 && isSameCall(call.Aux, "runtime.newobject")
2069 => mem
2070
2071 (NilCheck ptr:(SelectN [0] call:(StaticLECall _ _)) _)
2072 && isSameCall(call.Aux, "runtime.newobject")
2073 && warnRule(fe.Debug_checknil(), v, "removed nil check")
2074 => ptr
2075
2076 (NilCheck ptr:(OffPtr (SelectN [0] call:(StaticLECall _ _))) _)
2077 && isSameCall(call.Aux, "runtime.newobject")
2078 && warnRule(fe.Debug_checknil(), v, "removed nil check")
2079 => ptr
2080
2081 // Addresses of globals are always non-nil.
2082 (NilCheck ptr:(Addr {_} (SB)) _) => ptr
2083 (NilCheck ptr:(Convert (Addr {_} (SB)) _) _) => ptr
2084
2085 // Addresses of locals are always non-nil.
2086 (NilCheck ptr:(LocalAddr _ _) _)
2087 && warnRule(fe.Debug_checknil(), v, "removed nil check")
2088 => ptr
2089
2090 // Nil checks of nil checks are redundant.
2091 // See comment at the end of https://go-review.googlesource.com/c/go/+/537775.
2092 (NilCheck ptr:(NilCheck _ _) _ ) => ptr
2093
2094 // for late-expanded calls, recognize memequal applied to a single constant byte
2095 // Support is limited by 1, 2, 4, 8 byte sizes
2096 (StaticLECall {callAux} sptr (Addr {scon} (SB)) (Const64 [1]) mem)
2097 && isSameCall(callAux, "runtime.memequal")
2098 && symIsRO(scon)
2099 => (MakeResult (Eq8 (Load <typ.Int8> sptr mem) (Const8 <typ.Int8> [int8(read8(scon,0))])) mem)
2100
2101 (StaticLECall {callAux} (Addr {scon} (SB)) sptr (Const64 [1]) mem)
2102 && isSameCall(callAux, "runtime.memequal")
2103 && symIsRO(scon)
2104 => (MakeResult (Eq8 (Load <typ.Int8> sptr mem) (Const8 <typ.Int8> [int8(read8(scon,0))])) mem)
2105
2106 (StaticLECall {callAux} sptr (Addr {scon} (SB)) (Const64 [2]) mem)
2107 && isSameCall(callAux, "runtime.memequal")
2108 && symIsRO(scon)
2109 && canLoadUnaligned(config)
2110 => (MakeResult (Eq16 (Load <typ.Int16> sptr mem) (Const16 <typ.Int16> [int16(read16(scon,0,config.ctxt.Arch.ByteOrder))])) mem)
2111
2112 (StaticLECall {callAux} (Addr {scon} (SB)) sptr (Const64 [2]) mem)
2113 && isSameCall(callAux, "runtime.memequal")
2114 && symIsRO(scon)
2115 && canLoadUnaligned(config)
2116 => (MakeResult (Eq16 (Load <typ.Int16> sptr mem) (Const16 <typ.Int16> [int16(read16(scon,0,config.ctxt.Arch.ByteOrder))])) mem)
2117
2118 (StaticLECall {callAux} sptr (Addr {scon} (SB)) (Const64 [4]) mem)
2119 && isSameCall(callAux, "runtime.memequal")
2120 && symIsRO(scon)
2121 && canLoadUnaligned(config)
2122 => (MakeResult (Eq32 (Load <typ.Int32> sptr mem) (Const32 <typ.Int32> [int32(read32(scon,0,config.ctxt.Arch.ByteOrder))])) mem)
2123
2124 (StaticLECall {callAux} (Addr {scon} (SB)) sptr (Const64 [4]) mem)
2125 && isSameCall(callAux, "runtime.memequal")
2126 && symIsRO(scon)
2127 && canLoadUnaligned(config)
2128 => (MakeResult (Eq32 (Load <typ.Int32> sptr mem) (Const32 <typ.Int32> [int32(read32(scon,0,config.ctxt.Arch.ByteOrder))])) mem)
2129
2130 (StaticLECall {callAux} sptr (Addr {scon} (SB)) (Const64 [8]) mem)
2131 && isSameCall(callAux, "runtime.memequal")
2132 && symIsRO(scon)
2133 && canLoadUnaligned(config) && config.PtrSize == 8
2134 => (MakeResult (Eq64 (Load <typ.Int64> sptr mem) (Const64 <typ.Int64> [int64(read64(scon,0,config.ctxt.Arch.ByteOrder))])) mem)
2135
2136 (StaticLECall {callAux} (Addr {scon} (SB)) sptr (Const64 [8]) mem)
2137 && isSameCall(callAux, "runtime.memequal")
2138 && symIsRO(scon)
2139 && canLoadUnaligned(config) && config.PtrSize == 8
2140 => (MakeResult (Eq64 (Load <typ.Int64> sptr mem) (Const64 <typ.Int64> [int64(read64(scon,0,config.ctxt.Arch.ByteOrder))])) mem)
2141
2142 (StaticLECall {callAux} _ _ (Const64 [0]) mem)
2143 && isSameCall(callAux, "runtime.memequal")
2144 => (MakeResult (ConstBool <typ.Bool> [true]) mem)
2145
2146 (Static(Call|LECall) {callAux} p q _ mem)
2147 && isSameCall(callAux, "runtime.memequal")
2148 && isSamePtr(p, q)
2149 => (MakeResult (ConstBool <typ.Bool> [true]) mem)
2150
2151 // Turn known-size calls to memclrNoHeapPointers into a Zero.
2152 // Note that we are using types.Types[types.TUINT8] instead of sptr.Type.Elem() - see issue 55122 and CL 431496 for more details.
2153 (SelectN [0] call:(StaticCall {sym} sptr (Const(64|32) [c]) mem))
2154 && isInlinableMemclr(config, int64(c))
2155 && isSameCall(sym, "runtime.memclrNoHeapPointers")
2156 && call.Uses == 1
2157 && clobber(call)
2158 => (Zero {types.Types[types.TUINT8]} [int64(c)] sptr mem)
2159
2160 // Recognise make([]T, 0) and replace it with a pointer to the zerobase
2161 (StaticLECall {callAux} _ (Const(64|32) [0]) (Const(64|32) [0]) mem)
2162 && isSameCall(callAux, "runtime.makeslice")
2163 => (MakeResult (Addr <v.Type.FieldType(0)> {ir.Syms.Zerobase} (SB)) mem)
2164
2165 // Evaluate constant address comparisons.
2166 (EqPtr x x) => (ConstBool [true])
2167 (NeqPtr x x) => (ConstBool [false])
2168 (EqPtr (Addr {x} _) (Addr {y} _)) => (ConstBool [x == y])
2169 (EqPtr (Addr {x} _) (OffPtr [o] (Addr {y} _))) => (ConstBool [x == y && o == 0])
2170 (EqPtr (OffPtr [o1] (Addr {x} _)) (OffPtr [o2] (Addr {y} _))) => (ConstBool [x == y && o1 == o2])
2171 (NeqPtr (Addr {x} _) (Addr {y} _)) => (ConstBool [x != y])
2172 (NeqPtr (Addr {x} _) (OffPtr [o] (Addr {y} _))) => (ConstBool [x != y || o != 0])
2173 (NeqPtr (OffPtr [o1] (Addr {x} _)) (OffPtr [o2] (Addr {y} _))) => (ConstBool [x != y || o1 != o2])
2174 (EqPtr (LocalAddr {x} _ _) (LocalAddr {y} _ _)) => (ConstBool [x == y])
2175 (EqPtr (LocalAddr {x} _ _) (OffPtr [o] (LocalAddr {y} _ _))) => (ConstBool [x == y && o == 0])
2176 (EqPtr (OffPtr [o1] (LocalAddr {x} _ _)) (OffPtr [o2] (LocalAddr {y} _ _))) => (ConstBool [x == y && o1 == o2])
2177 (NeqPtr (LocalAddr {x} _ _) (LocalAddr {y} _ _)) => (ConstBool [x != y])
2178 (NeqPtr (LocalAddr {x} _ _) (OffPtr [o] (LocalAddr {y} _ _))) => (ConstBool [x != y || o != 0])
2179 (NeqPtr (OffPtr [o1] (LocalAddr {x} _ _)) (OffPtr [o2] (LocalAddr {y} _ _))) => (ConstBool [x != y || o1 != o2])
2180 (EqPtr (OffPtr [o1] p1) p2) && isSamePtr(p1, p2) => (ConstBool [o1 == 0])
2181 (NeqPtr (OffPtr [o1] p1) p2) && isSamePtr(p1, p2) => (ConstBool [o1 != 0])
2182 (EqPtr (OffPtr [o1] p1) (OffPtr [o2] p2)) && isSamePtr(p1, p2) => (ConstBool [o1 == o2])
2183 (NeqPtr (OffPtr [o1] p1) (OffPtr [o2] p2)) && isSamePtr(p1, p2) => (ConstBool [o1 != o2])
2184 (EqPtr (Const(32|64) [c]) (Const(32|64) [d])) => (ConstBool [c == d])
2185 (NeqPtr (Const(32|64) [c]) (Const(32|64) [d])) => (ConstBool [c != d])
2186 (EqPtr (Convert (Addr {x} _) _) (Addr {y} _)) => (ConstBool [x==y])
2187 (NeqPtr (Convert (Addr {x} _) _) (Addr {y} _)) => (ConstBool [x!=y])
2188
2189 (EqPtr (LocalAddr _ _) (Addr _)) => (ConstBool [false])
2190 (EqPtr (OffPtr (LocalAddr _ _)) (Addr _)) => (ConstBool [false])
2191 (EqPtr (LocalAddr _ _) (OffPtr (Addr _))) => (ConstBool [false])
2192 (EqPtr (OffPtr (LocalAddr _ _)) (OffPtr (Addr _))) => (ConstBool [false])
2193 (NeqPtr (LocalAddr _ _) (Addr _)) => (ConstBool [true])
2194 (NeqPtr (OffPtr (LocalAddr _ _)) (Addr _)) => (ConstBool [true])
2195 (NeqPtr (LocalAddr _ _) (OffPtr (Addr _))) => (ConstBool [true])
2196 (NeqPtr (OffPtr (LocalAddr _ _)) (OffPtr (Addr _))) => (ConstBool [true])
2197
2198 // Simplify address comparisons.
2199 (EqPtr (AddPtr p1 o1) p2) && isSamePtr(p1, p2) => (Not (IsNonNil o1))
2200 (NeqPtr (AddPtr p1 o1) p2) && isSamePtr(p1, p2) => (IsNonNil o1)
2201 (EqPtr (Const(32|64) [0]) p) => (Not (IsNonNil p))
2202 (NeqPtr (Const(32|64) [0]) p) => (IsNonNil p)
2203 (EqPtr (ConstNil) p) => (Not (IsNonNil p))
2204 (NeqPtr (ConstNil) p) => (IsNonNil p)
2205
2206 // Evaluate constant user nil checks.
2207 (IsNonNil (ConstNil)) => (ConstBool [false])
2208 (IsNonNil (Const(32|64) [c])) => (ConstBool [c != 0])
2209 (IsNonNil (Addr _) ) => (ConstBool [true])
2210 (IsNonNil (Convert (Addr _) _)) => (ConstBool [true])
2211 (IsNonNil (LocalAddr _ _)) => (ConstBool [true])
2212
2213 // Inline small or disjoint runtime.memmove calls with constant length.
2214 // See the comment in op Move in genericOps.go for discussion of the type.
2215 //
2216 // Note that we've lost any knowledge of the type and alignment requirements
2217 // of the source and destination. We only know the size, and that the type
2218 // contains no pointers.
2219 // The type of the move is not necessarily v.Args[0].Type().Elem()!
2220 // See issue 55122 for details.
2221 //
2222 // Because expand calls runs after prove, constants useful to this pattern may not appear.
2223 // Both versions need to exist; the memory and register variants.
2224 //
2225 // Match post-expansion calls, memory version.
2226 (SelectN [0] call:(StaticCall {sym} s1:(Store _ (Const(64|32) [sz]) s2:(Store _ src s3:(Store {t} _ dst mem)))))
2227 && sz >= 0
2228 && isSameCall(sym, "runtime.memmove")
2229 && s1.Uses == 1 && s2.Uses == 1 && s3.Uses == 1
2230 && isInlinableMemmove(dst, src, int64(sz), config)
2231 && clobber(s1, s2, s3, call)
2232 => (Move {types.Types[types.TUINT8]} [int64(sz)] dst src mem)
2233
2234 // Match post-expansion calls, register version.
2235 (SelectN [0] call:(StaticCall {sym} dst src (Const(64|32) [sz]) mem))
2236 && sz >= 0
2237 && call.Uses == 1 // this will exclude all calls with results
2238 && isSameCall(sym, "runtime.memmove")
2239 && isInlinableMemmove(dst, src, int64(sz), config)
2240 && clobber(call)
2241 => (Move {types.Types[types.TUINT8]} [int64(sz)] dst src mem)
2242
2243 // Match pre-expansion calls.
2244 (SelectN [0] call:(StaticLECall {sym} dst src (Const(64|32) [sz]) mem))
2245 && sz >= 0
2246 && call.Uses == 1 // this will exclude all calls with results
2247 && isSameCall(sym, "runtime.memmove")
2248 && isInlinableMemmove(dst, src, int64(sz), config)
2249 && clobber(call)
2250 => (Move {types.Types[types.TUINT8]} [int64(sz)] dst src mem)
2251
2252 // De-virtualize late-expanded interface calls into late-expanded static calls.
2253 (InterLECall [argsize] {auxCall} (Addr {fn} (SB)) ___) => devirtLECall(v, fn.(*obj.LSym))
2254
2255 // Move and Zero optimizations.
2256 // Move source and destination may overlap.
2257
2258 // Convert Moves into Zeros when the source is known to be zeros.
2259 (Move {t} [n] dst1 src mem:(Zero {t} [n] dst2 _)) && isSamePtr(src, dst2)
2260 => (Zero {t} [n] dst1 mem)
2261 (Move {t} [n] dst1 src mem:(VarDef (Zero {t} [n] dst0 _))) && isSamePtr(src, dst0)
2262 => (Zero {t} [n] dst1 mem)
2263 (Move {t} [n] dst (Addr {sym} (SB)) mem) && symIsROZero(sym) => (Zero {t} [n] dst mem)
2264
2265 // Don't Store to variables that are about to be overwritten by Move/Zero.
2266 (Zero {t1} [n] p1 store:(Store {t2} (OffPtr [o2] p2) _ mem))
2267 && isSamePtr(p1, p2) && store.Uses == 1
2268 && n >= o2 + t2.Size()
2269 && clobber(store)
2270 => (Zero {t1} [n] p1 mem)
2271 (Move {t1} [n] dst1 src1 store:(Store {t2} op:(OffPtr [o2] dst2) _ mem))
2272 && isSamePtr(dst1, dst2) && store.Uses == 1
2273 && n >= o2 + t2.Size()
2274 && disjoint(src1, n, op, t2.Size())
2275 && clobber(store)
2276 => (Move {t1} [n] dst1 src1 mem)
2277
2278 // Don't Move to variables that are immediately completely overwritten.
2279 (Zero {t} [n] dst1 move:(Move {t} [n] dst2 _ mem))
2280 && move.Uses == 1
2281 && isSamePtr(dst1, dst2)
2282 && clobber(move)
2283 => (Zero {t} [n] dst1 mem)
2284 (Move {t} [n] dst1 src1 move:(Move {t} [n] dst2 _ mem))
2285 && move.Uses == 1
2286 && isSamePtr(dst1, dst2) && disjoint(src1, n, dst2, n)
2287 && clobber(move)
2288 => (Move {t} [n] dst1 src1 mem)
2289 (Zero {t} [n] dst1 vardef:(VarDef {x} move:(Move {t} [n] dst2 _ mem)))
2290 && move.Uses == 1 && vardef.Uses == 1
2291 && isSamePtr(dst1, dst2)
2292 && clobber(move, vardef)
2293 => (Zero {t} [n] dst1 (VarDef {x} mem))
2294 (Move {t} [n] dst1 src1 vardef:(VarDef {x} move:(Move {t} [n] dst2 _ mem)))
2295 && move.Uses == 1 && vardef.Uses == 1
2296 && isSamePtr(dst1, dst2) && disjoint(src1, n, dst2, n)
2297 && clobber(move, vardef)
2298 => (Move {t} [n] dst1 src1 (VarDef {x} mem))
2299 (Store {t1} op1:(OffPtr [o1] p1) d1
2300 m2:(Store {t2} op2:(OffPtr [0] p2) d2
2301 m3:(Move [n] p3 _ mem)))
2302 && m2.Uses == 1 && m3.Uses == 1
2303 && o1 == t2.Size()
2304 && n == t2.Size() + t1.Size()
2305 && isSamePtr(p1, p2) && isSamePtr(p2, p3)
2306 && clobber(m2, m3)
2307 => (Store {t1} op1 d1 (Store {t2} op2 d2 mem))
2308 (Store {t1} op1:(OffPtr [o1] p1) d1
2309 m2:(Store {t2} op2:(OffPtr [o2] p2) d2
2310 m3:(Store {t3} op3:(OffPtr [0] p3) d3
2311 m4:(Move [n] p4 _ mem))))
2312 && m2.Uses == 1 && m3.Uses == 1 && m4.Uses == 1
2313 && o2 == t3.Size()
2314 && o1-o2 == t2.Size()
2315 && n == t3.Size() + t2.Size() + t1.Size()
2316 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4)
2317 && clobber(m2, m3, m4)
2318 => (Store {t1} op1 d1 (Store {t2} op2 d2 (Store {t3} op3 d3 mem)))
2319 (Store {t1} op1:(OffPtr [o1] p1) d1
2320 m2:(Store {t2} op2:(OffPtr [o2] p2) d2
2321 m3:(Store {t3} op3:(OffPtr [o3] p3) d3
2322 m4:(Store {t4} op4:(OffPtr [0] p4) d4
2323 m5:(Move [n] p5 _ mem)))))
2324 && m2.Uses == 1 && m3.Uses == 1 && m4.Uses == 1 && m5.Uses == 1
2325 && o3 == t4.Size()
2326 && o2-o3 == t3.Size()
2327 && o1-o2 == t2.Size()
2328 && n == t4.Size() + t3.Size() + t2.Size() + t1.Size()
2329 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5)
2330 && clobber(m2, m3, m4, m5)
2331 => (Store {t1} op1 d1 (Store {t2} op2 d2 (Store {t3} op3 d3 (Store {t4} op4 d4 mem))))
2332
2333 // Don't Zero variables that are immediately completely overwritten
2334 // before being accessed.
2335 (Move {t} [n] dst1 src1 zero:(Zero {t} [n] dst2 mem))
2336 && zero.Uses == 1
2337 && isSamePtr(dst1, dst2) && disjoint(src1, n, dst2, n)
2338 && clobber(zero)
2339 => (Move {t} [n] dst1 src1 mem)
2340 (Move {t} [n] dst1 src1 vardef:(VarDef {x} zero:(Zero {t} [n] dst2 mem)))
2341 && zero.Uses == 1 && vardef.Uses == 1
2342 && isSamePtr(dst1, dst2) && disjoint(src1, n, dst2, n)
2343 && clobber(zero, vardef)
2344 => (Move {t} [n] dst1 src1 (VarDef {x} mem))
2345 (Store {t1} op1:(OffPtr [o1] p1) d1
2346 m2:(Store {t2} op2:(OffPtr [0] p2) d2
2347 m3:(Zero [n] p3 mem)))
2348 && m2.Uses == 1 && m3.Uses == 1
2349 && o1 == t2.Size()
2350 && n == t2.Size() + t1.Size()
2351 && isSamePtr(p1, p2) && isSamePtr(p2, p3)
2352 && clobber(m2, m3)
2353 => (Store {t1} op1 d1 (Store {t2} op2 d2 mem))
2354 (Store {t1} op1:(OffPtr [o1] p1) d1
2355 m2:(Store {t2} op2:(OffPtr [o2] p2) d2
2356 m3:(Store {t3} op3:(OffPtr [0] p3) d3
2357 m4:(Zero [n] p4 mem))))
2358 && m2.Uses == 1 && m3.Uses == 1 && m4.Uses == 1
2359 && o2 == t3.Size()
2360 && o1-o2 == t2.Size()
2361 && n == t3.Size() + t2.Size() + t1.Size()
2362 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4)
2363 && clobber(m2, m3, m4)
2364 => (Store {t1} op1 d1 (Store {t2} op2 d2 (Store {t3} op3 d3 mem)))
2365 (Store {t1} op1:(OffPtr [o1] p1) d1
2366 m2:(Store {t2} op2:(OffPtr [o2] p2) d2
2367 m3:(Store {t3} op3:(OffPtr [o3] p3) d3
2368 m4:(Store {t4} op4:(OffPtr [0] p4) d4
2369 m5:(Zero [n] p5 mem)))))
2370 && m2.Uses == 1 && m3.Uses == 1 && m4.Uses == 1 && m5.Uses == 1
2371 && o3 == t4.Size()
2372 && o2-o3 == t3.Size()
2373 && o1-o2 == t2.Size()
2374 && n == t4.Size() + t3.Size() + t2.Size() + t1.Size()
2375 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5)
2376 && clobber(m2, m3, m4, m5)
2377 => (Store {t1} op1 d1 (Store {t2} op2 d2 (Store {t3} op3 d3 (Store {t4} op4 d4 mem))))
2378
2379 // Don't Move from memory if the values are likely to already be
2380 // in registers.
2381 (Move {t1} [n] dst p1
2382 mem:(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
2383 (Store {t3} op3:(OffPtr <tt3> [0] p3) d2 _)))
2384 && isSamePtr(p1, p2) && isSamePtr(p2, p3)
2385 && t2.Alignment() <= t1.Alignment()
2386 && t3.Alignment() <= t1.Alignment()
2387 && registerizable(b, t2)
2388 && registerizable(b, t3)
2389 && o2 == t3.Size()
2390 && n == t2.Size() + t3.Size()
2391 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2392 (Store {t3} (OffPtr <tt3> [0] dst) d2 mem))
2393 (Move {t1} [n] dst p1
2394 mem:(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
2395 (Store {t3} op3:(OffPtr <tt3> [o3] p3) d2
2396 (Store {t4} op4:(OffPtr <tt4> [0] p4) d3 _))))
2397 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4)
2398 && t2.Alignment() <= t1.Alignment()
2399 && t3.Alignment() <= t1.Alignment()
2400 && t4.Alignment() <= t1.Alignment()
2401 && registerizable(b, t2)
2402 && registerizable(b, t3)
2403 && registerizable(b, t4)
2404 && o3 == t4.Size()
2405 && o2-o3 == t3.Size()
2406 && n == t2.Size() + t3.Size() + t4.Size()
2407 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2408 (Store {t3} (OffPtr <tt3> [o3] dst) d2
2409 (Store {t4} (OffPtr <tt4> [0] dst) d3 mem)))
2410 (Move {t1} [n] dst p1
2411 mem:(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
2412 (Store {t3} op3:(OffPtr <tt3> [o3] p3) d2
2413 (Store {t4} op4:(OffPtr <tt4> [o4] p4) d3
2414 (Store {t5} op5:(OffPtr <tt5> [0] p5) d4 _)))))
2415 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5)
2416 && t2.Alignment() <= t1.Alignment()
2417 && t3.Alignment() <= t1.Alignment()
2418 && t4.Alignment() <= t1.Alignment()
2419 && t5.Alignment() <= t1.Alignment()
2420 && registerizable(b, t2)
2421 && registerizable(b, t3)
2422 && registerizable(b, t4)
2423 && registerizable(b, t5)
2424 && o4 == t5.Size()
2425 && o3-o4 == t4.Size()
2426 && o2-o3 == t3.Size()
2427 && n == t2.Size() + t3.Size() + t4.Size() + t5.Size()
2428 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2429 (Store {t3} (OffPtr <tt3> [o3] dst) d2
2430 (Store {t4} (OffPtr <tt4> [o4] dst) d3
2431 (Store {t5} (OffPtr <tt5> [0] dst) d4 mem))))
2432
2433 // Same thing but with VarDef in the middle.
2434 (Move {t1} [n] dst p1
2435 mem:(VarDef
2436 (Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
2437 (Store {t3} op3:(OffPtr <tt3> [0] p3) d2 _))))
2438 && isSamePtr(p1, p2) && isSamePtr(p2, p3)
2439 && t2.Alignment() <= t1.Alignment()
2440 && t3.Alignment() <= t1.Alignment()
2441 && registerizable(b, t2)
2442 && registerizable(b, t3)
2443 && o2 == t3.Size()
2444 && n == t2.Size() + t3.Size()
2445 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2446 (Store {t3} (OffPtr <tt3> [0] dst) d2 mem))
2447 (Move {t1} [n] dst p1
2448 mem:(VarDef
2449 (Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
2450 (Store {t3} op3:(OffPtr <tt3> [o3] p3) d2
2451 (Store {t4} op4:(OffPtr <tt4> [0] p4) d3 _)))))
2452 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4)
2453 && t2.Alignment() <= t1.Alignment()
2454 && t3.Alignment() <= t1.Alignment()
2455 && t4.Alignment() <= t1.Alignment()
2456 && registerizable(b, t2)
2457 && registerizable(b, t3)
2458 && registerizable(b, t4)
2459 && o3 == t4.Size()
2460 && o2-o3 == t3.Size()
2461 && n == t2.Size() + t3.Size() + t4.Size()
2462 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2463 (Store {t3} (OffPtr <tt3> [o3] dst) d2
2464 (Store {t4} (OffPtr <tt4> [0] dst) d3 mem)))
2465 (Move {t1} [n] dst p1
2466 mem:(VarDef
2467 (Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
2468 (Store {t3} op3:(OffPtr <tt3> [o3] p3) d2
2469 (Store {t4} op4:(OffPtr <tt4> [o4] p4) d3
2470 (Store {t5} op5:(OffPtr <tt5> [0] p5) d4 _))))))
2471 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5)
2472 && t2.Alignment() <= t1.Alignment()
2473 && t3.Alignment() <= t1.Alignment()
2474 && t4.Alignment() <= t1.Alignment()
2475 && t5.Alignment() <= t1.Alignment()
2476 && registerizable(b, t2)
2477 && registerizable(b, t3)
2478 && registerizable(b, t4)
2479 && registerizable(b, t5)
2480 && o4 == t5.Size()
2481 && o3-o4 == t4.Size()
2482 && o2-o3 == t3.Size()
2483 && n == t2.Size() + t3.Size() + t4.Size() + t5.Size()
2484 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2485 (Store {t3} (OffPtr <tt3> [o3] dst) d2
2486 (Store {t4} (OffPtr <tt4> [o4] dst) d3
2487 (Store {t5} (OffPtr <tt5> [0] dst) d4 mem))))
2488
2489 // Prefer to Zero and Store than to Move.
2490 (Move {t1} [n] dst p1
2491 mem:(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
2492 (Zero {t3} [n] p3 _)))
2493 && isSamePtr(p1, p2) && isSamePtr(p2, p3)
2494 && t2.Alignment() <= t1.Alignment()
2495 && t3.Alignment() <= t1.Alignment()
2496 && registerizable(b, t2)
2497 && n >= o2 + t2.Size()
2498 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2499 (Zero {t1} [n] dst mem))
2500 (Move {t1} [n] dst p1
2501 mem:(Store {t2} (OffPtr <tt2> [o2] p2) d1
2502 (Store {t3} (OffPtr <tt3> [o3] p3) d2
2503 (Zero {t4} [n] p4 _))))
2504 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4)
2505 && t2.Alignment() <= t1.Alignment()
2506 && t3.Alignment() <= t1.Alignment()
2507 && t4.Alignment() <= t1.Alignment()
2508 && registerizable(b, t2)
2509 && registerizable(b, t3)
2510 && n >= o2 + t2.Size()
2511 && n >= o3 + t3.Size()
2512 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2513 (Store {t3} (OffPtr <tt3> [o3] dst) d2
2514 (Zero {t1} [n] dst mem)))
2515 (Move {t1} [n] dst p1
2516 mem:(Store {t2} (OffPtr <tt2> [o2] p2) d1
2517 (Store {t3} (OffPtr <tt3> [o3] p3) d2
2518 (Store {t4} (OffPtr <tt4> [o4] p4) d3
2519 (Zero {t5} [n] p5 _)))))
2520 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5)
2521 && t2.Alignment() <= t1.Alignment()
2522 && t3.Alignment() <= t1.Alignment()
2523 && t4.Alignment() <= t1.Alignment()
2524 && t5.Alignment() <= t1.Alignment()
2525 && registerizable(b, t2)
2526 && registerizable(b, t3)
2527 && registerizable(b, t4)
2528 && n >= o2 + t2.Size()
2529 && n >= o3 + t3.Size()
2530 && n >= o4 + t4.Size()
2531 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2532 (Store {t3} (OffPtr <tt3> [o3] dst) d2
2533 (Store {t4} (OffPtr <tt4> [o4] dst) d3
2534 (Zero {t1} [n] dst mem))))
2535 (Move {t1} [n] dst p1
2536 mem:(Store {t2} (OffPtr <tt2> [o2] p2) d1
2537 (Store {t3} (OffPtr <tt3> [o3] p3) d2
2538 (Store {t4} (OffPtr <tt4> [o4] p4) d3
2539 (Store {t5} (OffPtr <tt5> [o5] p5) d4
2540 (Zero {t6} [n] p6 _))))))
2541 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5) && isSamePtr(p5, p6)
2542 && t2.Alignment() <= t1.Alignment()
2543 && t3.Alignment() <= t1.Alignment()
2544 && t4.Alignment() <= t1.Alignment()
2545 && t5.Alignment() <= t1.Alignment()
2546 && t6.Alignment() <= t1.Alignment()
2547 && registerizable(b, t2)
2548 && registerizable(b, t3)
2549 && registerizable(b, t4)
2550 && registerizable(b, t5)
2551 && n >= o2 + t2.Size()
2552 && n >= o3 + t3.Size()
2553 && n >= o4 + t4.Size()
2554 && n >= o5 + t5.Size()
2555 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2556 (Store {t3} (OffPtr <tt3> [o3] dst) d2
2557 (Store {t4} (OffPtr <tt4> [o4] dst) d3
2558 (Store {t5} (OffPtr <tt5> [o5] dst) d4
2559 (Zero {t1} [n] dst mem)))))
2560 (Move {t1} [n] dst p1
2561 mem:(VarDef
2562 (Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
2563 (Zero {t3} [n] p3 _))))
2564 && isSamePtr(p1, p2) && isSamePtr(p2, p3)
2565 && t2.Alignment() <= t1.Alignment()
2566 && t3.Alignment() <= t1.Alignment()
2567 && registerizable(b, t2)
2568 && n >= o2 + t2.Size()
2569 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2570 (Zero {t1} [n] dst mem))
2571 (Move {t1} [n] dst p1
2572 mem:(VarDef
2573 (Store {t2} (OffPtr <tt2> [o2] p2) d1
2574 (Store {t3} (OffPtr <tt3> [o3] p3) d2
2575 (Zero {t4} [n] p4 _)))))
2576 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4)
2577 && t2.Alignment() <= t1.Alignment()
2578 && t3.Alignment() <= t1.Alignment()
2579 && t4.Alignment() <= t1.Alignment()
2580 && registerizable(b, t2)
2581 && registerizable(b, t3)
2582 && n >= o2 + t2.Size()
2583 && n >= o3 + t3.Size()
2584 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2585 (Store {t3} (OffPtr <tt3> [o3] dst) d2
2586 (Zero {t1} [n] dst mem)))
2587 (Move {t1} [n] dst p1
2588 mem:(VarDef
2589 (Store {t2} (OffPtr <tt2> [o2] p2) d1
2590 (Store {t3} (OffPtr <tt3> [o3] p3) d2
2591 (Store {t4} (OffPtr <tt4> [o4] p4) d3
2592 (Zero {t5} [n] p5 _))))))
2593 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5)
2594 && t2.Alignment() <= t1.Alignment()
2595 && t3.Alignment() <= t1.Alignment()
2596 && t4.Alignment() <= t1.Alignment()
2597 && t5.Alignment() <= t1.Alignment()
2598 && registerizable(b, t2)
2599 && registerizable(b, t3)
2600 && registerizable(b, t4)
2601 && n >= o2 + t2.Size()
2602 && n >= o3 + t3.Size()
2603 && n >= o4 + t4.Size()
2604 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2605 (Store {t3} (OffPtr <tt3> [o3] dst) d2
2606 (Store {t4} (OffPtr <tt4> [o4] dst) d3
2607 (Zero {t1} [n] dst mem))))
2608 (Move {t1} [n] dst p1
2609 mem:(VarDef
2610 (Store {t2} (OffPtr <tt2> [o2] p2) d1
2611 (Store {t3} (OffPtr <tt3> [o3] p3) d2
2612 (Store {t4} (OffPtr <tt4> [o4] p4) d3
2613 (Store {t5} (OffPtr <tt5> [o5] p5) d4
2614 (Zero {t6} [n] p6 _)))))))
2615 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5) && isSamePtr(p5, p6)
2616 && t2.Alignment() <= t1.Alignment()
2617 && t3.Alignment() <= t1.Alignment()
2618 && t4.Alignment() <= t1.Alignment()
2619 && t5.Alignment() <= t1.Alignment()
2620 && t6.Alignment() <= t1.Alignment()
2621 && registerizable(b, t2)
2622 && registerizable(b, t3)
2623 && registerizable(b, t4)
2624 && registerizable(b, t5)
2625 && n >= o2 + t2.Size()
2626 && n >= o3 + t3.Size()
2627 && n >= o4 + t4.Size()
2628 && n >= o5 + t5.Size()
2629 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2630 (Store {t3} (OffPtr <tt3> [o3] dst) d2
2631 (Store {t4} (OffPtr <tt4> [o4] dst) d3
2632 (Store {t5} (OffPtr <tt5> [o5] dst) d4
2633 (Zero {t1} [n] dst mem)))))
2634
2635 (SelectN [0] call:(StaticLECall {sym} a x)) && needRaceCleanup(sym, call) && clobber(call) => x
2636 (SelectN [0] call:(StaticLECall {sym} x)) && needRaceCleanup(sym, call) && clobber(call) => x
2637
2638 // When rewriting append to growslice, we use as the new length the result of
2639 // growslice so that we don't have to spill/restore the new length around the growslice call.
2640 // The exception here is that if the new length is a constant, avoiding spilling it
2641 // is pointless and its constantness is sometimes useful for subsequent optimizations.
2642 // See issue 56440.
2643 // Note there are 2 rules here, one for the pre-decomposed []T result and one for
2644 // the post-decomposed (*T,int,int) result. (The latter is generated after call expansion.)
2645 (SliceLen (SelectN [0] (StaticLECall {sym} _ newLen:(Const(64|32)) _ _ _ _))) && isSameCall(sym, "runtime.growslice") => newLen
2646 (SelectN [1] (StaticCall {sym} _ newLen:(Const(64|32)) _ _ _ _)) && v.Type.IsInteger() && isSameCall(sym, "runtime.growslice") => newLen
2647
2648 // Collapse moving A -> B -> C into just A -> C.
2649 // Later passes (deadstore, elim unread auto) will remove the A -> B move, if possible.
2650 // This happens most commonly when B is an autotmp inserted earlier
2651 // during compilation to ensure correctness.
2652 // Take care that overlapping moves are preserved.
2653 // Restrict this optimization to the stack, to avoid duplicating loads from the heap;
2654 // see CL 145208 for discussion.
2655 (Move {t1} [s] dst tmp1 midmem:(Move {t2} [s] tmp2 src _))
2656 && t1.Compare(t2) == types.CMPeq
2657 && isSamePtr(tmp1, tmp2)
2658 && isStackPtr(src) && !isVolatile(src)
2659 && disjoint(src, s, tmp2, s)
2660 && (disjoint(src, s, dst, s) || isInlinableMemmove(dst, src, s, config))
2661 => (Move {t1} [s] dst src midmem)
2662
2663 // Same, but for large types that require VarDefs.
2664 (Move {t1} [s] dst tmp1 midmem:(VarDef (Move {t2} [s] tmp2 src _)))
2665 && t1.Compare(t2) == types.CMPeq
2666 && isSamePtr(tmp1, tmp2)
2667 && isStackPtr(src) && !isVolatile(src)
2668 && disjoint(src, s, tmp2, s)
2669 && (disjoint(src, s, dst, s) || isInlinableMemmove(dst, src, s, config))
2670 => (Move {t1} [s] dst src midmem)
2671
2672 // Don't zero the same bits twice.
2673 (Zero {t} [s] dst1 zero:(Zero {t} [s] dst2 _)) && isSamePtr(dst1, dst2) => zero
2674 (Zero {t} [s] dst1 vardef:(VarDef (Zero {t} [s] dst2 _))) && isSamePtr(dst1, dst2) => vardef
2675
2676 // Elide self-moves. This only happens rarely (e.g test/fixedbugs/bug277.go).
2677 // However, this rule is needed to prevent the previous rule from looping forever in such cases.
2678 (Move dst src mem) && isSamePtr(dst, src) => mem
2679
2680 // Constant rotate detection.
2681 ((Add64|Or64|Xor64) (Lsh64x64 x z:(Const64 <t> [c])) (Rsh64Ux64 x (Const64 [d]))) && c < 64 && d == 64-c && canRotate(config, 64) => (RotateLeft64 x z)
2682 ((Add32|Or32|Xor32) (Lsh32x64 x z:(Const64 <t> [c])) (Rsh32Ux64 x (Const64 [d]))) && c < 32 && d == 32-c && canRotate(config, 32) => (RotateLeft32 x z)
2683 ((Add16|Or16|Xor16) (Lsh16x64 x z:(Const64 <t> [c])) (Rsh16Ux64 x (Const64 [d]))) && c < 16 && d == 16-c && canRotate(config, 16) => (RotateLeft16 x z)
2684 ((Add8|Or8|Xor8) (Lsh8x64 x z:(Const64 <t> [c])) (Rsh8Ux64 x (Const64 [d]))) && c < 8 && d == 8-c && canRotate(config, 8) => (RotateLeft8 x z)
2685
2686 // Non-constant rotate detection.
2687 // We use shiftIsBounded to make sure that neither of the shifts are >64.
2688 // Note: these rules are subtle when the shift amounts are 0/64, as Go shifts
2689 // are different from most native shifts. But it works out.
2690 ((Add64|Or64|Xor64) left:(Lsh64x64 x y) right:(Rsh64Ux64 x (Sub64 (Const64 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x y)
2691 ((Add64|Or64|Xor64) left:(Lsh64x32 x y) right:(Rsh64Ux32 x (Sub32 (Const32 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x y)
2692 ((Add64|Or64|Xor64) left:(Lsh64x16 x y) right:(Rsh64Ux16 x (Sub16 (Const16 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x y)
2693 ((Add64|Or64|Xor64) left:(Lsh64x8 x y) right:(Rsh64Ux8 x (Sub8 (Const8 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x y)
2694
2695 ((Add64|Or64|Xor64) right:(Rsh64Ux64 x y) left:(Lsh64x64 x z:(Sub64 (Const64 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x z)
2696 ((Add64|Or64|Xor64) right:(Rsh64Ux32 x y) left:(Lsh64x32 x z:(Sub32 (Const32 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x z)
2697 ((Add64|Or64|Xor64) right:(Rsh64Ux16 x y) left:(Lsh64x16 x z:(Sub16 (Const16 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x z)
2698 ((Add64|Or64|Xor64) right:(Rsh64Ux8 x y) left:(Lsh64x8 x z:(Sub8 (Const8 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x z)
2699
2700 ((Add32|Or32|Xor32) left:(Lsh32x64 x y) right:(Rsh32Ux64 x (Sub64 (Const64 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x y)
2701 ((Add32|Or32|Xor32) left:(Lsh32x32 x y) right:(Rsh32Ux32 x (Sub32 (Const32 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x y)
2702 ((Add32|Or32|Xor32) left:(Lsh32x16 x y) right:(Rsh32Ux16 x (Sub16 (Const16 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x y)
2703 ((Add32|Or32|Xor32) left:(Lsh32x8 x y) right:(Rsh32Ux8 x (Sub8 (Const8 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x y)
2704
2705 ((Add32|Or32|Xor32) right:(Rsh32Ux64 x y) left:(Lsh32x64 x z:(Sub64 (Const64 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x z)
2706 ((Add32|Or32|Xor32) right:(Rsh32Ux32 x y) left:(Lsh32x32 x z:(Sub32 (Const32 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x z)
2707 ((Add32|Or32|Xor32) right:(Rsh32Ux16 x y) left:(Lsh32x16 x z:(Sub16 (Const16 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x z)
2708 ((Add32|Or32|Xor32) right:(Rsh32Ux8 x y) left:(Lsh32x8 x z:(Sub8 (Const8 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x z)
2709
2710 ((Add16|Or16|Xor16) left:(Lsh16x64 x y) right:(Rsh16Ux64 x (Sub64 (Const64 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x y)
2711 ((Add16|Or16|Xor16) left:(Lsh16x32 x y) right:(Rsh16Ux32 x (Sub32 (Const32 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x y)
2712 ((Add16|Or16|Xor16) left:(Lsh16x16 x y) right:(Rsh16Ux16 x (Sub16 (Const16 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x y)
2713 ((Add16|Or16|Xor16) left:(Lsh16x8 x y) right:(Rsh16Ux8 x (Sub8 (Const8 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x y)
2714
2715 ((Add16|Or16|Xor16) right:(Rsh16Ux64 x y) left:(Lsh16x64 x z:(Sub64 (Const64 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x z)
2716 ((Add16|Or16|Xor16) right:(Rsh16Ux32 x y) left:(Lsh16x32 x z:(Sub32 (Const32 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x z)
2717 ((Add16|Or16|Xor16) right:(Rsh16Ux16 x y) left:(Lsh16x16 x z:(Sub16 (Const16 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x z)
2718 ((Add16|Or16|Xor16) right:(Rsh16Ux8 x y) left:(Lsh16x8 x z:(Sub8 (Const8 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x z)
2719
2720 ((Add8|Or8|Xor8) left:(Lsh8x64 x y) right:(Rsh8Ux64 x (Sub64 (Const64 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x y)
2721 ((Add8|Or8|Xor8) left:(Lsh8x32 x y) right:(Rsh8Ux32 x (Sub32 (Const32 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x y)
2722 ((Add8|Or8|Xor8) left:(Lsh8x16 x y) right:(Rsh8Ux16 x (Sub16 (Const16 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x y)
2723 ((Add8|Or8|Xor8) left:(Lsh8x8 x y) right:(Rsh8Ux8 x (Sub8 (Const8 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x y)
2724
2725 ((Add8|Or8|Xor8) right:(Rsh8Ux64 x y) left:(Lsh8x64 x z:(Sub64 (Const64 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x z)
2726 ((Add8|Or8|Xor8) right:(Rsh8Ux32 x y) left:(Lsh8x32 x z:(Sub32 (Const32 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x z)
2727 ((Add8|Or8|Xor8) right:(Rsh8Ux16 x y) left:(Lsh8x16 x z:(Sub16 (Const16 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x z)
2728 ((Add8|Or8|Xor8) right:(Rsh8Ux8 x y) left:(Lsh8x8 x z:(Sub8 (Const8 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x z)
2729
2730 // Rotating by y&c, with c a mask that doesn't change the bottom bits, is the same as rotating by y.
2731 (RotateLeft64 x (And(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&63 == 63 => (RotateLeft64 x y)
2732 (RotateLeft32 x (And(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&31 == 31 => (RotateLeft32 x y)
2733 (RotateLeft16 x (And(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&15 == 15 => (RotateLeft16 x y)
2734 (RotateLeft8 x (And(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&7 == 7 => (RotateLeft8 x y)
2735
2736 // Rotating by -(y&c), with c a mask that doesn't change the bottom bits, is the same as rotating by -y.
2737 (RotateLeft64 x (Neg(64|32|16|8) (And(64|32|16|8) y (Const(64|32|16|8) [c])))) && c&63 == 63 => (RotateLeft64 x (Neg(64|32|16|8) <y.Type> y))
2738 (RotateLeft32 x (Neg(64|32|16|8) (And(64|32|16|8) y (Const(64|32|16|8) [c])))) && c&31 == 31 => (RotateLeft32 x (Neg(64|32|16|8) <y.Type> y))
2739 (RotateLeft16 x (Neg(64|32|16|8) (And(64|32|16|8) y (Const(64|32|16|8) [c])))) && c&15 == 15 => (RotateLeft16 x (Neg(64|32|16|8) <y.Type> y))
2740 (RotateLeft8 x (Neg(64|32|16|8) (And(64|32|16|8) y (Const(64|32|16|8) [c])))) && c&7 == 7 => (RotateLeft8 x (Neg(64|32|16|8) <y.Type> y))
2741
2742 // Rotating by y+c, with c a multiple of the value width, is the same as rotating by y.
2743 (RotateLeft64 x (Add(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&63 == 0 => (RotateLeft64 x y)
2744 (RotateLeft32 x (Add(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&31 == 0 => (RotateLeft32 x y)
2745 (RotateLeft16 x (Add(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&15 == 0 => (RotateLeft16 x y)
2746 (RotateLeft8 x (Add(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&7 == 0 => (RotateLeft8 x y)
2747
2748 // Rotating by c-y, with c a multiple of the value width, is the same as rotating by -y.
2749 (RotateLeft64 x (Sub(64|32|16|8) (Const(64|32|16|8) [c]) y)) && c&63 == 0 => (RotateLeft64 x (Neg(64|32|16|8) <y.Type> y))
2750 (RotateLeft32 x (Sub(64|32|16|8) (Const(64|32|16|8) [c]) y)) && c&31 == 0 => (RotateLeft32 x (Neg(64|32|16|8) <y.Type> y))
2751 (RotateLeft16 x (Sub(64|32|16|8) (Const(64|32|16|8) [c]) y)) && c&15 == 0 => (RotateLeft16 x (Neg(64|32|16|8) <y.Type> y))
2752 (RotateLeft8 x (Sub(64|32|16|8) (Const(64|32|16|8) [c]) y)) && c&7 == 0 => (RotateLeft8 x (Neg(64|32|16|8) <y.Type> y))
2753
2754 // Ensure we don't do Const64 rotates in a 32-bit system.
2755 (RotateLeft64 x (Const64 <t> [c])) && config.PtrSize == 4 => (RotateLeft64 x (Const32 <t> [int32(c)]))
2756 (RotateLeft32 x (Const64 <t> [c])) && config.PtrSize == 4 => (RotateLeft32 x (Const32 <t> [int32(c)]))
2757 (RotateLeft16 x (Const64 <t> [c])) && config.PtrSize == 4 => (RotateLeft16 x (Const32 <t> [int32(c)]))
2758 (RotateLeft8 x (Const64 <t> [c])) && config.PtrSize == 4 => (RotateLeft8 x (Const32 <t> [int32(c)]))
2759
2760 // Rotating by c, then by d, is the same as rotating by c+d.
2761 // We're trading a rotate for an add, which seems generally a good choice. It is especially good when c and d are constants.
2762 // This rule is a bit tricky as c and d might be different widths. We handle only cases where they are the same width.
2763 (RotateLeft(64|32|16|8) (RotateLeft(64|32|16|8) x c) d) && c.Type.Size() == 8 && d.Type.Size() == 8 => (RotateLeft(64|32|16|8) x (Add64 <c.Type> c d))
2764 (RotateLeft(64|32|16|8) (RotateLeft(64|32|16|8) x c) d) && c.Type.Size() == 4 && d.Type.Size() == 4 => (RotateLeft(64|32|16|8) x (Add32 <c.Type> c d))
2765 (RotateLeft(64|32|16|8) (RotateLeft(64|32|16|8) x c) d) && c.Type.Size() == 2 && d.Type.Size() == 2 => (RotateLeft(64|32|16|8) x (Add16 <c.Type> c d))
2766 (RotateLeft(64|32|16|8) (RotateLeft(64|32|16|8) x c) d) && c.Type.Size() == 1 && d.Type.Size() == 1 => (RotateLeft(64|32|16|8) x (Add8 <c.Type> c d))
2767
2768 // Loading constant values from dictionaries and itabs.
2769 (Load <typ.BytePtr> (OffPtr [off] (Addr {s} sb) ) _) && isFixedSym(s, off) => (Addr {fixedSym(b.Func, s, off)} sb)
2770 (Load <typ.BytePtr> (OffPtr [off] (Convert (Addr {s} sb) _) ) _) && isFixedSym(s, off) => (Addr {fixedSym(b.Func, s, off)} sb)
2771 (Load <typ.BytePtr> (OffPtr [off] (ITab (IMake (Addr {s} sb) _))) _) && isFixedSym(s, off) => (Addr {fixedSym(b.Func, s, off)} sb)
2772 (Load <typ.BytePtr> (OffPtr [off] (ITab (IMake (Convert (Addr {s} sb) _) _))) _) && isFixedSym(s, off) => (Addr {fixedSym(b.Func, s, off)} sb)
2773 (Load <typ.Uintptr> (OffPtr [off] (Addr {s} sb) ) _) && isFixedSym(s, off) => (Addr {fixedSym(b.Func, s, off)} sb)
2774 (Load <typ.Uintptr> (OffPtr [off] (Convert (Addr {s} sb) _) ) _) && isFixedSym(s, off) => (Addr {fixedSym(b.Func, s, off)} sb)
2775 (Load <typ.Uintptr> (OffPtr [off] (ITab (IMake (Addr {s} sb) _))) _) && isFixedSym(s, off) => (Addr {fixedSym(b.Func, s, off)} sb)
2776 (Load <typ.Uintptr> (OffPtr [off] (ITab (IMake (Convert (Addr {s} sb) _) _))) _) && isFixedSym(s, off) => (Addr {fixedSym(b.Func, s, off)} sb)
2777
2778 // Loading constant values from runtime._type.hash.
2779 (Load <t> (OffPtr [off] (Addr {sym} _) ) _) && t.IsInteger() && t.Size() == 4 && isFixed32(config, sym, off) => (Const32 [fixed32(config, sym, off)])
2780 (Load <t> (OffPtr [off] (Convert (Addr {sym} _) _) ) _) && t.IsInteger() && t.Size() == 4 && isFixed32(config, sym, off) => (Const32 [fixed32(config, sym, off)])
2781 (Load <t> (OffPtr [off] (ITab (IMake (Addr {sym} _) _))) _) && t.IsInteger() && t.Size() == 4 && isFixed32(config, sym, off) => (Const32 [fixed32(config, sym, off)])
2782 (Load <t> (OffPtr [off] (ITab (IMake (Convert (Addr {sym} _) _) _))) _) && t.IsInteger() && t.Size() == 4 && isFixed32(config, sym, off) => (Const32 [fixed32(config, sym, off)])
2783
2784 // Calling cmpstring a second time with the same arguments in the
2785 // same memory state can reuse the results of the first call.
2786 // See issue 61725.
2787 // Note that this could pretty easily generalize to any pure function.
2788 (SelectN [0] (StaticLECall {f} x y (SelectN [1] c:(StaticLECall {g} x y mem))))
2789 && isSameCall(f, "runtime.cmpstring")
2790 && isSameCall(g, "runtime.cmpstring")
2791 => @c.Block (SelectN [0] <typ.Int> c)
2792
2793 // If we don't use the result of cmpstring, might as well not call it.
2794 // Note that this could pretty easily generalize to any pure function.
2795 (SelectN [1] c:(StaticLECall {f} _ _ mem)) && c.Uses == 1 && isSameCall(f, "runtime.cmpstring") && clobber(c) => mem
2796
2797 // We can easily compute the result of efaceeq if
2798 // we know the underlying type is pointer-ish.
2799 (StaticLECall {f} typ_ x y mem)
2800 && isSameCall(f, "runtime.efaceeq")
2801 && isDirectType(typ_)
2802 && clobber(v)
2803 => (MakeResult (EqPtr x y) mem)
2804
2805 // We can easily compute the result of ifaceeq if
2806 // we know the underlying type is pointer-ish.
2807 (StaticLECall {f} itab x y mem)
2808 && isSameCall(f, "runtime.ifaceeq")
2809 && isDirectIface(itab)
2810 && clobber(v)
2811 => (MakeResult (EqPtr x y) mem)
2812
2813 // If we use the result of slicebytetostring in a map lookup operation,
2814 // then we don't need to actually do the []byte->string conversion.
2815 // We can just use the ptr/len of the byte slice directly as a (temporary) string.
2816 //
2817 // Note that this does not handle some obscure cases like
2818 // m[[2]string{string(b1), string(b2)}]. There is code in ../walk/order.go
2819 // which handles some of those cases.
2820 (StaticLECall {f} [argsize] typ_ map_ key:(SelectN [0] sbts:(StaticLECall {g} _ ptr len mem)) m:(SelectN [1] sbts))
2821 && (isSameCall(f, "runtime.mapaccess1_faststr")
2822 || isSameCall(f, "runtime.mapaccess2_faststr")
2823 || isSameCall(f, "runtime.mapdelete_faststr"))
2824 && isSameCall(g, "runtime.slicebytetostring")
2825 && key.Uses == 1
2826 && sbts.Uses == 2
2827 && resetCopy(m, mem)
2828 && clobber(sbts)
2829 && clobber(key)
2830 => (StaticLECall {f} [argsize] typ_ map_ (StringMake <typ.String> ptr len) mem)
2831
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